Page 1 70001 and up • This shop manual may contain attachments and optional equipment that are not available in your area. Please consult your local Komatsu distributor for those items you may require. Materials and specifications are subject to change without notice. •...
Page 2 CONTENTS No. of page GENERAL ................01-1 STRUCTURE AND FUNCTION ..........10-1 TESTING AND ADJUSTING ..........20-1 DISASSEMBLY AND ASSEMBLY ........30-1 MAINTENANCE STANDARD..........40-1 OTHERS ................90-1 00-2 D155AX-5...
Page 3 10-88 10-133 10-176 01-11 10-44 10-89 10-134 10-177 01-12 10-46 10-91 10-135 10-178 10- 1 10-47 10-92 10-136 10-179 10- 2 10-93 10-137 10-180 10-48 10- 3 10-49 10-94 10-138 10-181 10- 4 10-95 10-139 10-182 10-50 00-2-1 00-3 D155AX-5...
Page 4 20-119 20-212 20-251 20-424 ‡ ‡ ﬁ 20-120 20-214 20-252 20-425 ﬁ 20-121 20-215 20-253 20-426 ﬁ 20-122 20-216 20-254 20-427 ﬁ 20-123 20-217 20-255 20-428 ﬁ 20-124 20-218 20-256 20-429 ‡ ﬁ 20-125 20-219 20-257 20-430 00-4 00-2-2 D155AX-5...
Page 5 30- 59 ﬁ ﬁ 20-615 20-737 20-848 30- 60 ﬁ ﬁ 20-616 20-738 20-849 30- 61 ﬁ ﬁ 20-617 20-739 20-850 30- 62 ﬁ ﬁ 20-618 20-740 20-851 30- 63 ﬁ ﬁ 20-619 20-741 20-901 30- 64 00-2-3 00-5 D155AX-5...
Page 6 30-116 30-271 40- 24 30-156 30-214 30-117 30-157 30-215 30-272 40- 25 30-118 30-273 40- 26 30-158 30-216 30-119 30-159 30-217 30-274 40- 28 30-120 30-275 40- 29 30-160 30-218 40- 29-1 3 30-121 30-161 30-219 30-276 00-6 00-2-4 D155AX-5...
Page 7 40-56 40-57 40-58 40-59 40-60 40-61 40-62 40-63 40-64 40-66 40-67 40-68 40-69 40-70 40-71 40-72 40-73 40-74 40-75 40-76 40-78 40-79 90- 1 90- 3 90- 5 90- 7 90- 9 90-11 90-13 90-15 90-17 90-19 00-2-5 00-7 D155AX-5...
Page 8 00-8 00-2-6 (Blank page) D155AX-5...
Page 9 When checking the water level, always wait for the water to cool down. If the radiator cap is removed when the water is still hot, the water will spurt out and cause burns. ¤ Be careful not to get caught in the fan or other rotating parts. 20-1 D155AX-5...
Page 10 STANDARD VALUE TABLE STANDARD VALUE TABLE FOR ENGINE STANDARD VALUE TABLE FOR ENGINE Serial No. 70001 – 75000 Machine model D155AX-5 Engine SA6D140E-2 Standard value Item Measurement conditions Unit Service limit value for new machine 2,050 ± 50 — High idling —...
Page 11 STANDARD VALUE TABLE STANDARD VALUE TABLE FOR ENGINE Serial No. 75001 and up Machine model D155AX-5 Engine SA6D140E-3 Standard value Item Measurement conditions Unit Service limit value for new machine 2,100 ± 50 — High idling — Engine speed Low idling 1,900 —...
Page 12 20-2-2 D155AX-5 (Blank page)
Page 13 STANDARD VALUE TABLE STANDARD VALUE TABLE FOR CHASSIS STANDARD VALUE TABLE FOR CHASSIS Machine model D155AX-5 Cate- Standard value Service limit Measurement conditions Unit Item gory for new machine value • Engine oil pressure: Torque converter stall 1,580 ± 100...
Page 14 STANDARD VALUE TABLE STANDARD VALUE TABLE FOR CHASSIS Machine model D155AX-5 Cate- Standard value Service limit Unit Item Measurement conditions gory for new machine value 53.9 ± 19.1 78.4 • Engine stopped N ↔ FORWARD {5.5 ± 2.0} {8.0} • Center of lever...
Page 15 STANDARD VALUE TABLE STANDARD VALUE TABLE FOR CHASSIS Machine model D155AX-5 Cate- Standard value Service limit Measurement conditions Item Unit gory of new machine value Work equipment posture 2.5 ± 0.5 Ripper LIFT TYD00007 • Engine at high idling • Hydraulic oil temperature: 3.0 ±...
Page 16 2) Insert T- 20 – 30 V Between (2) – (1) adapter. Steering circuit oil Measure CN-STHP2 pressure sensor B voltage Engine stopped 0.8 – 1.2 V Between (3) – (1) Engine running + 4.0 – 4.6 V Steering relief 20-8 D155AX-5...
Page 17 If the condition is as shown in the 1) Turn starting table below, it is normal switch OFF. 2) Disconnect CN-246 Measure Pin puller solenoid Between (1) – (2) 40 – 80 Ω connectors. (male) resistance Between (1), (2) – chassis Min. 1 MΩ 20-15 D155AX-5...
Page 18 2) Disconnect connector. Min. 1 MΩ Engine stopped CN-406 Measure HSS charge circuit Between oil pressure sensor (male) resistance (1) – (2) Engine running Max. 1 Ω Between (1), (2) – chassis Min. 1 MΩ 20-16 D155AX-5...
Page 19 If the condition is as shown in the running table below, it is normal 2) Insert T- Measure Engine speed CN-ST3 adaper. Between (4) – (12) 0.5 – 3.0 V voltage sensor ﬂ When using circuit tester, select AC voltage range. 20-17 D155AX-5...
Page 20 2) Insert T- Measure Lever at N or Backup alarm Between CN-ST2 adapter. 20 – 30 V voltage FORWARD switch (7) – 3) Turn joystick Lever chassis Max. 1 V to directional at REVERSE position. 20-18 D155AX-5...
Page 21 2) Insert T- Lever at 1st or Measure Between adapter. 20 – 30 V 2nd switch CN-ST2 voltage ST2(14) – 3) Turn joystick Lever at 3rd chassis Max. 1 V to 2nd or 1st position. 20-19 D155AX-5...
Page 22 OFF. 2) Disconnect Approx. 75 kΩ conectors. (female) Fuel level Measure Between Approx. 50 kΩ Level 3/7 sensor resistance (female) CN2 (3) – Level 5/7 Approx. 35 kΩ CN1 (2) Approx. 14 kΩ 20-20 D155AX-5...
Page 23 Max. 1 V turned ON 1) Insert T- If the condition is as shown in the adapter. table below, it is normal Measure 2) Turn starting S-NET voltage Between (9) (10) – (8) switch ON. 4.0 – 10.0 V 20-21 D155AX-5...
Page 24 If the condition is as shown in the 1) Insert T- table below, it is normal adapter. Measure While engine is Alternator Max. 1 V Between voltage stopped (4) – (2) While engine is 27.5 – 29.5 V running 20-22 D155AX-5...
Page 25 Testing location causing hydraulic drift of blade and ripper ............... 20-152 Measuring leakage inside hydraulic cylinder ..................20-153 Releasing remaining oil pressure in hydraulic cylinder ............... 20-154 Bleeding air from hydraulic cylinder ..................... 20-154 Adjusting work equipment safety lever ....................20-155 Adjusting semi-U tiltdozer ........................20-156 20-101 D155AX-5...
Page 26 0 – 490N {0 – 50kg} Commercially Stroke, hydraulic drift Scale available Commercially Work equipment speed Stop watch available Measuring voltage and 79A-264-0211 Tester resistance 799-601-8000 T-adapter Troubleshooting of wiring harnesses 799-601-7360 Adapter For 5 pins relay ª1: SA6D140E-2 engine 20-102 D155AX-5...
Page 27 Set the fuel control lever to the high idling position, then measure the engine speed. ﬂ When measuring the “stall speed of torque con- verter” and “speed to stall the torque converter and relieve the work equipment pump”, see the measurement procedure for them. TLD00010 20-103 D155AX-5...
Page 28 ﬂ The engine speed is indicated by the unit of rpm. Measuring low idling speed: Set the joystick and work equipment con- trol lever in neutral and set the fuel con- trol dial in the low idling position. 20-103-1 D155AX-5...
Page 29 8) After measuring the engine speed, turn OFF service switch (2) and set the panel to the ordinary mode. 9) Install cover (1). 20-103-2 D155AX-5...
Page 30 ﬂ The normal intake air pressure (boost pres- sure) must be measured while the machine is operating at the rated output. An ap- proximate value can be obtained in the field, however, by measuring when the torque converter stalls. 20-104 D155AX-5...
Page 31 ﬂ The normal intake air pressure (boost pres- sure) must be measured while the machine is operating at the rated output. An ap- proximate value can be obtained in the field, however, by measuring when the torque converter stalls. 20-104-1 D155AX-5...
Page 32 TESTING AND ADJUSTING 20-104-2 (Blank page) D155AX-5...
Page 33 (intake air tem- perature of the engine). Accordingly, if any abnormal value is obtained, carry out tem- perature compensation by the following cal- culation. • Compensation value [°C] = Measured value + 2 x (20 – Ambient air tempera- ture) 20-105 D155AX-5...
Page 34 (intake air tem- perature of the engine). Accordingly, if any abnormal value is obtained, carry out tem- perature compensation by the following cal- culation. • Compensation value [°C] = Measured value + 2 x (20 – Ambient air tempera- ture) 20-105-1 D155AX-5...
Page 35 MEASURING EXHAUST COLOR TESTING AND ADJUSTING 20-105-2 (Blank page) D155AX-5...
Page 36 7) Place the filter paper used to catch the ex- haust has color on top of at least 10 sheets of unused filter paper inside the filter paper holder, and read the value shown. 20-106 D155AX-5...
Page 37 120° each time and adjust the clearance of the valves of each cylinder ac- cording the firing order. • Firing order: 1-5-3-6-2-4 ﬂ After tightening the locknut, check the clear- ance again. 20-107 D155AX-5...
Page 38 2 to 4 to adjust the valves of each cylinder ac- cording to the firing order. ﬂ Firing order: 1–5–3–6–2–4 6. After completing the measurement, set to the original condition. 3 Cylinder head cover mounting bolt: 29.4 – 34.3 Nm {3.0 – 3.5 kgm} 20-107-1 D155AX-5...
Page 39 TESTING AND ADJUSTING 20-107-2 (Blank page) D155AX-5...
Page 40 MEASURING COMPRESSION PRESSURE Serial No.: 75001 and up ﬂ For the method of measuring the compression pressure, see the Engine Shop Manual for the 140-3 Series. 20-108 D155AX-5...
Page 41 ﬂ Blow-by varies greatly according to the con- dition of the engine. Therefore, if the blow- by value is considered abnormal, check for problems connected with defective blow-by, such as excessive oil consumption, defec- tive exhaust gas color, and prematurely dirty or deteriorated oil. 20-109 D155AX-5...
Page 42 ﬂ Blow-by varies greatly according to the con- dition of the engine. Therefore, if the blow- by value is considered abnormal, check for problems connected with defective blow-by, such as excessive oil consumption, defec- tive exhaust gas color, and prematurely dirty or deteriorated oil. 20-109-1 D155AX-5...
Page 43 MEASURING ENGINE OIL PRESSURE TESTING AND ADJUSTING 20-109-2 (Blank page) D155AX-5...
Page 44 1. Remove engine oil pressure pickup plug (1) (PT1/ 2. Install nipple 1of oil pressure gauge H1, then connect to oil pressure gauge H2 (0.98MPa {10kg/cm 3. Start the engine, and measure the oil pressure with the engine at low idling and high idling. 20-110 D155AX-5...
Page 45 4. After completing the measurement, remove the measurement equipment and set to the original condition. 3 Oil pressure switch: 2.9 – 5.9 Nm {0.3 – 0.6 kgm} 20-110-1 D155AX-5...
Page 46 TESTING AND ADJUSTING FUEL INJECTION TIMING TESTING AND ADJUSTING 20-110-2 (Blank page) D155AX-5...
Page 47 Engine Shop Manual. Serial No. 75001 and up ﬂ Since the match mark on the timing gear case is matched to the key way of the supply pump drive shaft, ADJUSTMENT OF FUEL INJECTION TIMMING is not necessary. 20-111 D155AX-5...
Page 48 ﬂ Precautions when replacing fuel filter cartrige out inspection of the fuel system or removal Always use a genuine Komatsu part for the or installation of the equipment. Always fol- fuel filter cartrige. low the following precautions when carrying With the common rail type fuel injection sys- out the operation.
Page 49 2. Fit nipple 1 of pressure test kit A,then connect to the pressure test kit. 3. Start the engine and measure the fuel pressure at high idling. 4. After completing the measurement, remove the measurement equipment and set to the original condition. 20-111-2 D155AX-5...
Page 50 (3) to the left to select an injector to be disabled. ﬂ The flashing bit display unit indicates each injector No. 1: No. 1 injector 2: No. 2 injector 3: No. 3 injector 4: No. 4 injector 20-111-3 D155AX-5...
Page 51 ﬂ The flashing speed becomes normal and the selected injector(s) start(s) operating again. ﬂ If the system goes out of this mode, the reduced cylinder mode operation is re- set. 4) Turn OFF service switch (2). 5) Install cover (1). 20-111-4 D155AX-5...
Page 52 When fuel comes out, install the plug. pressure circuit, so repeat the procedure 3 Air bleed plug: from Step 2. 7.8 – 9.8 Nm {0.8 – 1.0 kgm} 20-111-5 D155AX-5...
Page 53 8. Start the engine, run it at high idling, then apply load to the engine. ﬂ If this inspection is carried out with the engine mounted on the machine, stall the torque converter or relieve the hydraulic pump. 20-111-6 D155AX-5...
Page 54 1) Loosen 2 mounting bolts of alternator (1) and 1 lock bolt of the bar. 2) Loosen locknut (2), move alternator (1) with adjustment nut (3), adjust the tension of belt (4). ﬂ Deflection (one belt): 13 – 16 mm 20-112 D155AX-5...
Page 55 1. Loosen four mounting bolts (4) and locknut (2). 2. Turn adjustment bolt (3) and shift air conditioner compressor assembly (4) to adjust the belt ten- sion. 3. Tighten locknut (2) and four mounting bolts (1). 20-112-1 D155AX-5...
Page 56 2) Tighten stopper bolt (2) until it contacts bracket (3). 3) Tighten stopper bolt (2) a futher 2 turns and hold in position with locknut (4). 3 Locknut: 245.0 – 308.7 Nm {35.0 – 31.5 kgm} 20-112-2 D155AX-5...
Page 57 (2) to adjust clearance a. • Clearance a: 0.75 – 1.0mm 3. Tighten locknut (3). 9 Locknut: 69 – 74Nm {7.0 – 7.5kgm} ﬂ Install the sensor wiring carefully so that an ex- cessive force will not be applied to it. 20-113 D155AX-5...
Page 58 3. When a T-adapter has been inserted or con- nected to the applicable connector to carry out troubleshooting, never start the engine. ﬂ If the starting switch is operated, operate it only to OFF or ON. Never turn it to the START position. 20-113-1 D155AX-5...
Page 59 MEASURING EXHAUST COLOR TESTING AND ADJUSTING 20-113-2 (Blank page) D155AX-5...
Page 60 ADJUSTING FUEL CONTROL LEVER AND DECELERATOR PEDAL TESTING AND ADJUSTING ADJUSTING FUEL CONTROL LEVER AND DECELERATOR PEDAL Serial No. 70001 – 75000 20-114 D155AX-5...
Page 61 FULL position, and check that the engine speed is at least 1000 rpm. ﬂ If the engine speed is below 1000 rpm,adjust by extending installation di- mension a of rod (1) to make the engine speed more than 1000 rpm. 20-115 D155AX-5...
Page 62 Set the fuel control dial to the high idling posi- tion and check that the high idling speed is corect. • High idling speed: 2,050 rpm ﬂ If engine speed is too low: Adjust the high idling speed with stopper bolt (3). 20-116 D155AX-5...
Page 63 ﬂ After finishing the measurement, return the joystick to the neutral position immediately, then lower the transmission oil temperature with the engine at high idling. 20-117 D155AX-5...
Page 64 ﬂ After completion of the measurement, re- turn the full monolever swiftly to neutral, and run the engine at high idling to lower the power train oil temperature. 20-117-1 D155AX-5...
Page 65 MEASURING ENGINE OIL PRESSURE TESTING AND ADJUSTING 20-117-2 (Blank page) D155AX-5...
Page 66 ﬂ After finishing the measurement, return the joystick to the neutral position immediately, then lower the transmission oil temperature with the engine at high idling. 20-118 D155AX-5...
Page 67 ﬂ After finishing measurement, return the joy- stick into neutral immediately and lower the power train oil temperature at high idling. 20-118-1 D155AX-5...
Page 68 TESTING AND ADJUSTING FUEL INJECTION TIMING TESTING AND ADJUSTING 20-118-2 (Blank page) D155AX-5...
Page 69 TESTING AND ADJUSTING ADJUSTING STEERING NEUTRAL POSITION ADJUSTING STEERING NEUTRAL POSITION ﬂ The figure shows for serial No. 70001 – 75000. 20-135 D155AX-5...
Page 70 In this case, if the engine starts, the machine starts a spin-turn slowly. Secure the safety around the machine. ﬂ After lifting up the machine body, stop the engine. 2. Setting machine to adjustment mode 1) Remove controller cover (1). 20-136 D155AX-5...
Page 71 If the machine body cannot be lifted up, the work may be performed without lifting it up. In this case, if the engine starts, the machine starts a spin-turn slowly. Secure the safety around the machine. ﬂ After lifting up the machine body, stop the engine. 20-138-1 D155AX-5...
Page 72 (7) at this time. Similarly, turn the steering lever to the right end and return it into neutral and measure value (7) at this time. Compare these values with each other. 20-138-2 D155AX-5...
Page 73 2) After confirming the travel deviation direc- tion, lower the machine body to the ground by using the blade and ripper. 5. Finishing adjustment mode 1) Turn service switch (2) OFF. 2) Install cover (1). 20-138-3 D155AX-5...
Page 74 TESTING AND ADJUSTING 20-138-4 (Blank page) D155AX-5...
Page 75 2) Disconnect CN1 connector (1), CN-2H1 con- nector (2), and CN-2H2 connector (3) from the HSS controller. 3) Disconnect CN-LPL connector (4) from the ROPS bracket, then connect the emergency steering switch (5) to the male connector and female connector. 20-139 D155AX-5...
Page 76 ﬂ Operating directions of switch and steer- ing directions Position Forward Reverse Steering to left Steering to right Steering to right Steering to left 20-140 D155AX-5...
Page 77 2) Disconnect CN-ST1 connector (1), CN-ST3 connector (2), and CN-ST2 connector (3) from the HSS controller. 3) Disconnect CN-LPL connector (4) from the ROPS bracket, then connect the emergency steering switch (5) to the male connector and female connector. 20-140-1 D155AX-5...
Page 78 ﬂ Operating directions of switch and steer- ing directions Position Forward Reverse Steering to left Steering to right Steering to right Steering to left 20-140-2 D155AX-5...
Page 79 "CC". 2. Operation in initial current adjustment mode 1) After adjustment mode "CC" is displayed, turn the lever in the direction to change the initial current. 2) Lever current (7) in mV is displayed. 20-140-3 D155AX-5...
Page 80 3) After the target current is obtained, turn buzzer cancel switch (3) to the right to save the value. ﬂ The buzzer makes a pip. 3. Finishing adjustment mode 1) Turn service switch (2) OFF. 2) Install cover (1). 20-140-4 D155AX-5...
Page 81 2. When tension is low Supply grease through valve (2). ﬂ If the track shoe is not tensed well, slowly move the machine forward and backward. ﬂ After adjusting the tension, check it again ac- cording to the testing procedure shown above. 20-145 D155AX-5...
Page 82 2. Measuring load sensing pressure 1) Remove the control valve cover. 2) Remove oil pressure pickup plug (2) (10 x 1.25). 20-146 D155AX-5...
Page 83 Troubleshooting of monitor system (M mode) (Serial No. 75001 and up) ........20-701 Troubleshooting of engine controller system (G mode) ..............20-801 Troubleshooting of HSS controller and electrical system (E mode) (Serial No. 75001 and up) ..20-901 20-201 D155AX-5...
Page 84 To prevent this, always investigate why the prob- Has the same kind of failure occurred be- lem occurred. Then, remove the root cause. fore? Check before troubleshooting Check for symptoms of any abnormality in the machine. Check the CHECKS BEFORE STARTING items. 20-202 D155AX-5...
Page 85 TROUBLESHOOTING 20-213 D155AX-5 (Blank page)
Page 86 Heater relay terminal A CN-260 — Starting switch terminal BR — CN-108 — Heater relay terminal B CN-262 Intermediate connector CN-109 — Heater relay terminal C CN-263 Ripper pin-puller switch Single pin CN-110 Intermediate connector CN-264 Intermediate connector connector 20-214 D155AX-5...
Page 87 TROUBLESHOOTING TYPE OF CONNECTOR AND POSITION OF INSTALLATION 20-219 D155AX-5...
Page 88 CN-201 Intermediate connector CN-364 Windshield washer (Rear) CN-203 Right headlamp CN-391 Air conditioner relay CN-204 Left headlamp CN-392 CN-204 Air conditioner blower motor Air conditioner compressor 1-pin Air conditioner thermostat & CN-393 CN-205 Horn connector dual pressure switch 20-219-1 D155AX-5...
Page 89 CN-E31 Injector #1 CN-X2 – Mode selector switch CN-E32 Injector #2 CN-ST1 – HSS controller CN-E33 Injector #3 CN-ST2 – HSS controller CN-E34 Injector #4 CN-ST3 – HSS controller CN-E35 Injector #5 CN-T01 Monitor panel CN-E36 Injector #6 20-219-2 D155AX-5...
Page 90 TROUBLESHOOTING TYPE OF CONNECTOR AND POSITION OF INSTALLATION 20-219-3 D155AX-5...
Page 91 TROUBLESHOOTING TYPE OF CONNECTOR AND POSITION OF INSTALLATION 20-219-4 D155AX-5...
Page 92 TROUBLESHOOTING TYPE OF CONNECTOR AND POSITION OF INSTALLATION 20-219-5 D155AX-5...
Page 93 TROUBLESHOOTING TYPE OF CONNECTOR AND POSITION OF INSTALLATION 20-219-6 D155AX-5...
Page 94 ﬂ The terms male and female refer to the pins, while the terms male housing and female housing refer to the mating portion of the housing. X type connector pins Male (female housing) Female (male housing) TEW00221 TEW00222 TEW00223 TEW00224 TEW00225 TEW00226 20-220 D155AX-5...
Page 95 TROUBLESHOOTING CONNECTION TABLE FOR CONNECTOR PIN NUMBERS Relay connector pins Male (female housing) Female (male housing) BLP00073 BLP00074 BLP00075 BLP00076 20-229 D155AX-5...
Page 96 CONNECTION TABLE FOR CONNECTOR PIN NUMBERS Type HD30 series connector Shell size Body (Plug) Body (Receptacle) code Pin (male terminal) Pin (female terminal) 18-8 Pin (female terminal) Pin (male terminal) Pin (male terminal) Pin (female terminal) 18-14 Pin (female terminal) Pin (male terminal) 20-229-1 D155AX-5...
Page 97 CONNECTION TABLE FOR CONNECTOR PIN NUMBERS Type HD30 series connector Shell size Body (Plug) Body (Receptacle) code Pin (male terminal) Pin (female terminal) 18-20 Pin (female terminal) Pin (male terminal) Pin (male terminal) Pin (female terminal) 18-21 Pin (female terminal) Pin (male terminal) 20-229-2 D155AX-5...
Page 98 CONNECTION TABLE FOR CONNECTOR PIN NUMBERS Type HD30 series connector Shell size Body (Plug) Body (Receptacle) code Pin (male terminal) Pin (female terminal) 24-9 Pin (female terminal) Pin (male terminal) Pin (male terminal) Pin (female terminal) 24-16 Pin (female terminal) Pin (male terminal) 20-229-3 D155AX-5...
Page 99 CONNECTION TABLE FOR CONNECTOR PIN NUMBERS Type HD30 series connector Shell size Body (Plug) Body (Receptacle) code Pin (male terminal) Pin (female terminal) 24-21 Pin (female terminal) Pin (male terminal) Pin (male terminal) Pin (female terminal) 24-23 Pin (female terminal) Pin (male terminal) 20-229-4 D155AX-5...
Page 100 TROUBLESHOOTING CONNECTION TABLE FOR CONNECTOR PIN NUMBERS Type HD30 series connector Shell size Body (Plug) Body (Receptacle) code Pin (male terminal) Pin (female terminal) 24-31 Pin (female terminal) Pin (male terminal) 20-229-5 D155AX-5...
Page 101 TROUBLESHOOTING CONNECTION TABLE FOR CONNECTOR PIN NUMBERS [Number is printed on each connector (Wire inserting end).] DT, DT-T series connector pins Body (Plug) Body (Receptacle) 20-229-6 D155AX-5...
Page 102 TROUBLESHOOTING CONNECTION TABLE FOR CONNECTOR PIN NUMBERS [Number is printed on each connector (Wire inserting end).] DT, DT-T series connector pins Body (Plug) Body (Receptacle) 20-229-7 D155AX-5...
Page 103 TROUBLESHOOTING CONNECTION TABLE FOR CONNECTOR PIN NUMBERS [Number is printed on each connector (Wire inserting end).] DTM series connector pins Body (Plug) Body (Receptacle) 20-229-8 D155AX-5...
Page 104 TROUBLESHOOTING CONNECTION TABLE FOR CONNECTOR PIN NUMBERS DTHD series connector pins Body (Plug) Body (Receptacle) 20-229-9 D155AX-5...
Page 105 20-229-10 D155AX-5 (Blank page)
Page 106 TESTING AND ADJUSTING FUNCTION OF ELECTRONIC CONTROL SYSTEM FUNCTION OF ELECTRONIC CONTROL SYSTEM Serial No. 70001 – 75000 20-230 D155AX-5...
Page 107 • The monitor panel communicates with the HSS controller through the network circuit (S-NET). Upon receiving an abnormality sig- nal from the HSS controller, the monitor panel turns on the electric system caution lamp and alarm buzzer. 20-231 D155AX-5...
Page 108 TROUBLESHOOTING FUNCTION OF ELECTRONIC CONTROL SYSTEM Serial No. 75001 and up 20-231-1 D155AX-5...
Page 109 • The monitor panel communicates with the HSS controller through the network circuit (S-NET). Upon receiving an abnormality sig- nal from the HSS controller, the monitor panel turns on the electric system caution lamp and alarm buzzer. 20-231-2 D155AX-5...
Page 110 TESTING AND ADJUSTING DISPLAY OF HSS CONTROLLER DISPLAY OF HSS CONTROLLER Serial No. 70001 – 75000 20-232 D155AX-5...
Page 111 S: Turn the starting switch to the ON position. S+: Turn the starting switch to the ON position, then operate the concerned switch or lever. E: Start the engine. E+: Start the engine, then operate the concerned switch or lever. 20-235 D155AX-5...
Page 112 E: Error which is occurring currently, P: Error which occurred in past = Code and service meter reading at time of occurrence of error are displayed alternately. Sending of items = Buzzer cancel switch, Clearing code (history) = Mode selector switch ﬂ3: Adjustment mode Sending of items = Buzzer cancel switch 20-235-1 D155AX-5...
Page 113 TROUBLESHOOTING DISPLAY AND SPECIAL FUNCTIONS OF MONITOR PANEL Selection of each mode 20-235-2 D155AX-5...
Page 114 A user code is displayed only when an error of high importance is detected. An error may have occurred even if a user code is not displayed. Accordingly, if you feel any abnormality, be sure to check for a service code in the service code display mode. 20-235-3 D155AX-5...
Page 115 Abnormality in steering position 1 system • Abnormality in forward-reverse travel sensor Stop the machine immediately and call a serv- iceman. ﬁ ﬁ CALL • Abnormality in control power source • Abnormality in steering position 2 system • Abnormality in engine pump 20-235-4 D155AX-5...
Page 116 1) Monitoring code (5) 2) Monitoring mode mark (6) (Lamp on the left side) lights up. 3) Monitor information (7) 20-235-5 D155AX-5...
Page 117 Engine controller program version – Engine controller Monitor panel tachometer module program version – Monitor panel Monitor panel caution module program version – Monitor panel HSS controller program version – HSS controller Fuel level sensor voltage Monitor panel 20-235-6 D155AX-5...
Page 118 2: Reverse travel command 3: 1st gear speed command 4: 2nd gear speed command 5: 3rd gear speed command 6: (Unused) ﬂ The state of the "forward 1st gear speed" is shown as an example in the figure at right. 20-235-7 D155AX-5...
Page 119 If any service code is not saved, "– –" is dis- played in the upper display unit. 1) Output error No. is displayed (8). 2) Service code mark (9) lights up. 3) Service code (10). 4) Time when error occurred is displayed (11). 20-235-8 D155AX-5...
Page 120 Disconnection in fuel injector No. 4 system G mode E0465 Disconnection in fuel injector No. 5 system G mode E0466 Disconnection in fuel injector No. 6 system G mode E0468 Overcurrent in fuel supply pump PCV1 system G mode CALL03 20-235-9 D155AX-5...
Page 121 Short circuit in HSS pump solenoid A system E mode CALL03 E0774 Disconnection in HSS pump solenoid B system E mode CALL03 E0775 Short circuit in HSS pump solenoid B system E mode CALL03 E0930 Abnormality in engine speed sensor system E mode 20-235-10 D155AX-5...
Page 122 3) Reproduce the all service codes which have been displayed. ﬂ For the reproduction method, see the above list or the text of troubleshooting. 4) Confirm that the service codes are "displayed" or "not displayed" in the service code display unit. 20-235-11 D155AX-5...
Page 123 (For details of usage of this mode, see TESTING AND ADJUSTING.) This mode is used to stop one or more injectors of a common rail Reduced cylinder engine to find out an abnormal injector. mode (For details of usage of this mode, see TESTING AND ADJUSTING.) 20-235-12 D155AX-5...
Page 124 When there is S: If the solenoid valve input voltage is not turned on/off normally, go to the trouble code at the bottom of the judgment table. If the solenoid valve input voltage is turned on/off normally, go to the right of the table further. 20-236 D155AX-5...
Page 125 TESTING AND ADJUSTING 20-237 D155AX-5 (Blank page)
Page 126 Hydraulic drift is large in ripper lifting direction. Blade pitch does not work normally (When equipped with pitch dozer). Ripper pin puller does not work normally (When equipped with giant ripper). Abnormal sound comes out of work equipment pump. Troubleshooting code 20-238 D155AX-5...
Page 127 H-10 ‡ ‡ E-28 H-11 H-12 H-13 H-14 H-15 H-16 H-17 H-18 H-19 ♦ H-20 ♦ H-21 H-22 E-10 E-11 E-12 E-13 E-14 E-15 E-16 E-17 E-18 E-19 E-20 E-21 E-22 E-23 E-24 E-25 E-26 E-27 E-29 E-30 20-239 D155AX-5...
Page 128 When carrying out troubleshooting, see this chart for details of the connector pin number and location for inspection and measurement of the wiring connector number appearing in the troubleshooting flow chart for each failure mode (problem). 20-240 D155AX-5...
Page 129 ﬂ Before carrying out troubleshooting, check that all the related connectors are properly inserted. ﬂ Always connect any disconnected connectors before going on the next step. 20-251 D155AX-5...
Page 130 ª When engine controller detects abnormality in network • When service code E0436 is displayed singly Abnormality in network 1. Defective engine controller E0436 system • When service code E0436 is displayed together with E0101, E0104, and E0105 ﬂ Same as each service code 20-252 D155AX-5...
Page 131 3. Lock-up lamp goes off. 1. Gear speed cannot be displayed. 2. Tachometer is not displayed. 3. Lock-up lamp goes off. 1. Gear speed cannot be displayed. 2. Tachometer is not displayed. 3. Warning lamp and buzzer do not work. 20-253 D155AX-5...
Page 132 TROUBLESHOOTING N MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM N MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM Engine controller system 20-254 D155AX-5...
Page 133 As the network is monitored by multiple devices as explained above, if any abnormality occurs in the network system, multiple service codes are displayed simultaneously. It is important to understand which system each service code indicates by using the monitoring mode, etc. before starting troubleshooting. 20-255 D155AX-5...
Page 134 CN-ST1 (female) (1), (12) and CN2 • Disconnect T01 and CN1. replace - CN-ST1 (female) (1), (12) - CN2 (female) • Max. 1 Ω (female) (8), (18) normal? (8), (18) Defective engine Replace controller N-1. Related electrical circuit diagram 20-256 D155AX-5...
Page 135 T01 (10) and T01 (female) (11), (12) • Disconnect T01 and CN1. replace • Max. 1 Ω (female) (10) - T01 (female) (11), (12) normal? Defective monitor panel (caution Replace module) N-2. Related electrical circuit diagram 20-257 D155AX-5...
Page 136 Repair or in wiring harness between T01 • Disconnect T01 and CN1. (9) and CN-ST1 (female) (1) normal? replace (female) (9) - ST1 (female) (1) • Max. 1 Ω Defective HSS controller Replace N-3. Related electrical circuit diagram 20-258 D155AX-5...
Page 137 T01 (9) - CN-ST1 (female) (1), or • Min. 7.5 V between CN-ST1 (female) (12) - CN-2 (female) (8), (13) Defective monitor panel (tachom- Replace eter module) N-4. Related electrical circuit diagram 20-259 D155AX-5...
Page 138 [E0104], and [E0105] displayed, too? Go to N-4 Is any one of service codes [E0101], Turn starting switch ON. • Defective HSS controller Replace [E0104], and [E0105] displayed, too? Go to N-1, 2, or 3 according to displayed service code 20-260 D155AX-5...
Page 139 Is resistance between T01 (female) • Disconnect T01 and CN-ST1. wiring harness between T01 (female) (9) replace (9) and CN-ST1 (female) (1) normal? • Max. 1 Ω and CN-ST1 (female) (1) Defective HSS Replace controller N-6. Related electrical circuit diagram 20-261 D155AX-5...
Page 140 [E0104], and [E0105] displayed, too? Go to N-4 Is any one of service codes [E0101], • Turn starting switch ON. Defective engine controller Replace [E0104], and [E0105] displayed, too? Go to N-1, 2, or 3 according to displayed service code 20-262 D155AX-5...
Page 141 Oil level rises (water or fuel mixed with oil) ................. 20-319 S-14 Water temperature becomes too high (overheating) ............20-320 S-15 Abnormal noise is made ......................20-321 S-16 Vibration is excessive ....................... 20-322 ﬂ Serial No. 75001 and up: See 140-3 series engine shop manual. 20-301 D155AX-5...
Page 142 [Troubleshooting] Troubleshooting is carried out in the order of (1) (2) (3) probability, starting with the causes that have been marked as having the highest probability from information gained from [Questions] and [Check items]. 20-302 D155AX-5...
Page 143 E-29. Blade pitch does not work normally (When equipped with pitch dozer) ......20-442 E-30. Ripper pin puller does not work normally (When equipped with giant ripper) ....20-444 E-31. Engine does not start (Engine does not rotate) ............... 20-446 20-401 D155AX-5...
Page 144 4.1 – 4.3V potentiometer potentiometer CN-STR (3) When machine is fully steered to right: system 1 3. Defective contact or disconnection in wiring harness be- 0.73 – 0.89V tween controller CN-2H1 (9) – potentiometer CN-STR (1) 4. Defective HSS controller 20-402 D155AX-5...
Page 145 M-18. Head lamps or rear lamps do not light up ................. 20-624 M-19. Automatic preheating is not carried out when preheating switch is turned to AUTO .. 20-626 M-20. Window wipers and window washers do not work ............20-628 M-21. Air conditioner does not work ....................20-632 20-601 D155AX-5...
Page 146 ELECTRICAL CIRCUIT DIAGRAM FOR M MODE TROUBLESHOOTING ELECTRICAL CIRCUIT DIAGRAM FOR M MODE Monitor panel system 20-602 D155AX-5...
Page 147 ﬂ Before carrying out troubleshooting, check that all the related connectors are properly inserted. ﬂ Always connect any disconnected connectors before going on the next step. 20-701 D155AX-5...
Page 148 1. Lowering of engine oil pressure 2. Defective engine oil pressure sensor Abnormality in engine CALL E0430 oil pressure ª When engine water temperature caution lamp on monitor panel flashes 1. Defective engine water temperature sensor Abnormality in engine E0432 water temperature 20-702 D155AX-5...
Page 149 When engine speed is above about 1,300 rpm: Min. 1 MΩ 1. Turns on caution lamp and caution • Sensor resistance (10 - 100˚C) High-temperature sensor: 90 k - 3.5 Ω buzzer. Low-temperature sensor: 9 k - 0.3 Ω 20-703 D155AX-5...
Page 150 TROUBLESHOOTING M MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM M MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM Monitor panel system 20-704 D155AX-5...
Page 151 TROUBLESHOOTING M MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM 20-705 D155AX-5...
Page 152 CN2 voltage between CN2 (female) (7) • Turn starting switch ON. replace • Max. 1 V and chassis ground normal? (female) (7) - 251 (female) (2) Defective monitor panel (caution Replace module) M-1. Related electrical circuit diagram 20-706 D155AX-5...
Page 153 CN2 (female) (8) • Turn starting switch ON. replace (female) (8) - 222 (5) - 21A (female) • Max. 1 V and chassis ground normal? Defective monitor panel (caution Replace module) M-2. Related electrical circuit diagram 20-707 D155AX-5...
Page 154 Note: This means that the HSS oil temperature sensor has detected abnormal temperature but the display of the monitor panel has become normal. Accordingly, inspect the HSS oil temperature system and remove the cause of the abnormal temperature. 20-708 D155AX-5...
Page 155 Defective monitor panel (caution Replace module) Note: This means that the engine water temperature sensor has detected abnormal temperature but the display of the monitor panel has become normal. Accordingly, inspect the engine and remove the cause of the abnormal temperature. 20-709 D155AX-5...
Page 156 CN1 (female) (1) chassis ground normal? replace • 20 - 30 V - fuse 6 Disconnection or defective contact Repair or in wiring harness between CN1 replace (female) (2) - chassis ground M-7 a). Related electrical circuit diagram 20-710 D155AX-5...
Page 157 T01 replace • 20 - 30 V chassis ground normal? (female) (7) - fuse 10 Disconnection or defective contact Repair or in wiring harness between T01 replace (female) (2) - chassis ground M-7 b). Related electrical circuit diagram 20-711 D155AX-5...
Page 158 Caution module (Gage and lamp display unit) does not go off. Cause Remedy Defective monitor panel (caution Replace module) b) The tachometer module (tachometer and service meter display unit) does not go off. Cause Remedy Defective monitor panel (caution Replace module) 20-712 D155AX-5...
Page 159 • Turn starting switch ON. between CN1 (female) (4) and replace (female) (4) - T01 (female) (4) - ANR • Max. 1 V chassis ground normal? - M2 (female) (2) - 220 (male) (2) Defective diode (220) Replace 20-713 D155AX-5...
Page 160 TROUBLESHOOTING M-9 b). Related electrical circuit diagram 20-714 D155AX-5...
Page 161 Delta connection CN1 (female) (4) - • Start engine (at medium or between CN1 (female) (4) and chassis replace higher speed). ground normal? • 20 - 30 V Defective monitor panel (Tachom- Replace eter module) M-10 a). Related electrical circuit diagram 20-715 D155AX-5...
Page 162 When short connector is connected to 453. Replace module) to 453 (female), does lamp go off? • Start engine. Check according to Defective power train oil tempera- standard values ture sensor table, then replace M-10 c). Related electrical circuit diagram 20-716 D155AX-5...
Page 163 Is resistance between CN1 (female) in wiring harness between CN1 • Disconnect CN1. (5) and chassis ground normal? replace • Max. 1 Ω (female) (5) - 452 (female) (1) Defective monitor panel (Caution Replace module) M-10 d). Related electrical circuit diagram 20-717 D155AX-5...
Page 164 (female) and chassis ground replace (female) (2) - GND2 (chassis • Max. 1 Ω normal? ground) Disconnection or defective contact Repair or in wiring harness between CN1 replace (female) (8) - CN-406 (female) (1) M-11. Related electrical circuit diagram 20-718 D155AX-5...
Page 165 Is voltage between CN2 (female) (5) in wiring harness between CN2 • Turn starting switch ON. replace and chassis ground normal? (female) (5) - ribbon heater • Max. 1 V Defective monitor panel (Caution Replace module) M-12. Related electrical circuit diagram 20-719 D155AX-5...
Page 166 When 21A (monitor side) is disconnected, is Repair or • Disconnect 21A and CN2. resistance between CN2 (female) (8) and wiring harness between CN2 (female) (8) replace • Max. 1 Ω chassis ground normal? - 21A Defective caution buzzer Replace 20-720 D155AX-5...
Page 167 TROUBLESHOOTING M-13 M-13. Related electrical circuit diagram 20-721 D155AX-5...
Page 168 • Turn starting switch OFF. Repair or wiring harness between CN2 (female) (7) between CN2 (female) (7) and chassis • Disconnect 251 and CN2. replace - 251 (female) (2) • Max. 1 MΩ ground normal? Defective caution lamp Replace 20-722 D155AX-5...
Page 169 TROUBLESHOOTING M-14 M-14. Related electrical circuit diagram 20-723 D155AX-5...
Page 170 Is water temperature sensor of engine • Turn starting switch ON. controller is judged defective by troubleshooting? Check according to Defective engine water temperature standard values sensor table, then replace Is N mode normal? Check N mode. Defective monitor panel (Caution Replace module) 20-724 D155AX-5...
Page 171 When 453 is disconnected, is resistance Repair or wiring harness between CN2 • Disconnect 453 and CN2. between CN2 (female) (2) and chassis replace • Min. 1 MΩ ground normal? (female) (2) - 453 (female) (1) Defective monitor panel (Caution Replace module) 20-725 D155AX-5...
Page 172 TROUBLESHOOTING M-16. Related electrical circuit diagram 20-726 D155AX-5...
Page 173 • Disconnect CN2 and 423. (3) and 423 (female) (1) normal? replace wiring harness between CN2 • Max. 1 Ω (female) (3) - 423 (female) (1) Defective monitor panel (Caution Replace module) 20-727 D155AX-5...
Page 174 TROUBLESHOOTING M-17 M-17. Related electrical circuit diagram 20-728 D155AX-5...
Page 175 Abnormality in network system Go to N-3 M-19. Service meter does not advance while engine is running Cause Remedy Is sandglass displayed in service • Start engine. Go to M10 a) meter unit? Defective monitor panel (Tachom- Replace eter module) 20-729 D155AX-5...
Page 176 Is resistance between X1 (2) and (3) • Turn service switch OFF. Defective service switch Replace normal? • Min. 1 MΩ Short circuit with chassis ground in Repair or wiring harness between T01 replace (female) (5) - X1 (3) 20-730 D155AX-5...
Page 177 TROUBLESHOOTING M-20 M-20. Related electrical circuit diagram 20-731 D155AX-5...
Page 178 CN4 (female) (2) Replace • Turn starting switch OFF. (2) and chassis ground normal? - chassis ground • Max. 1 Ω Disconnection or defective contact in wiring Repair or harness between CN4 (female) (1) - 211 replace (female) (2) 20-732 D155AX-5...
Page 179 TROUBLESHOOTING M-21. Related electrical circuit diagram 20-733 D155AX-5...
Page 180 Is voltage between T01 (6) and wiring harness between T01 (female) (6) • Turn headlamp switch ON. Replace chassis ground normal? - CN-211 (female) (2) • 20 - 30 V Defective monitor panel Replace M-22. Related electrical circuit diagram 20-734 D155AX-5...
Page 181 (2) and (3) normal? • Turn headlamp switch ON. • Max. 1 Ω Disconnection or defective contact Repair or in wiring harness between CN-211 replace (female) (2) - CN-203 (female) (1) or CN-204 (female) (1) M-23 a). Related electrical circuit diagram 20-735 D155AX-5...
Page 182 • Turn rear lamp switch ON. • Max. 1 Ω Disconnection or defective contact Repair or in wiring harness between CN-216 replace (female) (2) - CN-224 (female) (1) or CN-248 (female) (1) M-23 b). Related electrical circuit diagram 20-736 D155AX-5...
Page 183 Disconnection or defective contact in Repair or Is voltage between CN-109 and • Turn starting switch ON. wiring harness between CN-214 (female) replace chassis ground normal? • 20 - 30 V (10) - CN-109 Defective heater relay Replace 20-737 D155AX-5...
Page 184 TROUBLESHOOTING M-24 M-24. Related electrical circuit diagram 20-738 D155AX-5...
Page 185 • Turn starting switch OFF. in wiring harness between switch Repair or • Disconnect connector. (female) (4) and motor connector (female) connector (female) (4) - motor replace • Max. 1 Ω (2) normal? connector (female) (2) Defective wiper motor Replace 20-739 D155AX-5...
Page 186 (female) (2) and chassis • Disconnect connector. connector (female) (2) - CN-SX8 replace ground normal? • Max. 1 Ω (chassis ground) Disconnection or defective contact in wiring harness between switch Repair or connector (female) (1) - motor replace connector (female) (1) 20-740 D155AX-5...
Page 187 TROUBLESHOOTING M-25 M-25. Related electrical circuit diagram 20-741 D155AX-5...
Page 188 • Turn starting switch ON. Is voltage between CN-39 (4) and • Set blower switch to position other Replace Defective air conditioner relay chassis ground normal? than OFF. • 20 - 30 V See next page A 20-742 D155AX-5...
Page 189 • Turn starting switch OFF. Repair or (female) (1) and CN-395 (female) (2) in wiring harness between CN-394 • Disconnect CN-394 and CN-395. replace • Max. 1 Ω normal? (female) (1) - CN-395 (female) (2) Go to b) Replace 20-743 D155AX-5...
Page 190 (female) (2) - CN-398 (female) (3) normal? • Max. 1 Ω • Turn starting switch OFF. Is resistance between CN-398 (male) • Disconnect CN-398. Defective clutch relay Replace (1) and (3) normal? • 240 ± 40 Ω See next page A 20-744 D155AX-5...
Page 191 Is voltage between CN-ARC (2) and • For condition, see note. in wiring harness between CN-215 replace chassis ground normal? • 20 - 30 V (male) (7) - CN-ARC (female) (2) Defective air conditioner fan motor Replace or compressor 20-745 D155AX-5...
Page 192 TROUBLESHOOTING M-26 M-26. Related electrical circuit diagram 20-746 D155AX-5...
Page 193 ﬂ Before carrying out troubleshooting, check that all the related connectors are properly inserted. ﬂ Always connect any disconnected connectors before going on the next step. 20-801 D155AX-5...
Page 194 9. Short circuit with chassis ground or power source in wiring harness between controller CN-7 (9) (- side) - injector No. 6 (2) 10. Disconnection or defective contact in wiring harness between controller CN-7 (5), (13) - chassis ground 11. Defective engine controller 20-802 D155AX-5...
Page 195 2. Stops outputting to fuel supply pump played) Between CN-E35 (1) - (2): 0.4 - 1.1 Ω • Injector No. 3 resistance and all fuel injectors (When E0458 is also displayed) Between CN-E36 (1) - (2): 0.4 - 1.1 Ω 20-803 D155AX-5...
Page 196 CN-7 (4) (+ side) - PCV2 solenoid CN-E42 (1) supply pump PCV2 E0470 3. Short circuit with power source in wiring harness between controller CN-7 (12) (- side) - system PCV2 solenoid CN-E42 (2) 4. Defective engine controller 20-804 D155AX-5...
Page 197 Between CN-E42 (1) - (2): 2.3 - 5.3 Ω ror is displayed singly) (When error is displayed singly) 2. Engine stops (When E0469 is also dis- 2. Stops outputting to PCV1 and PCV2 played) (When E0469 is also displayed) 20-805 D155AX-5...
Page 198 1. Defective low-pressure fuel circuit 2. Defective fuel supply pump PCV 3. Defective pressure limiter 4. Defective common rail fuel pressure sensor No-pressure feed by E0483 fuel supply pump 1 5. Defective fuel injector 6. Leakage from high-pressure fuel piping 20-806 D155AX-5...
Page 199 1. Operates machine with output lim- ited 1. Stops outputting to fuel supply pump 1. Output is lowered 2. Stops outputting to fuel injector 1. Output is lowered 1. Derates engine output 2. Operates machine with output lim- ited 20-807 D155AX-5...
Page 200 E0490 lator switch signal 1. Defective starting switch 2. Short circuit with power source in wiring harness between controller CN-4 (2) - starting Short circuit in starting switch terminal C E0491 switch C system 3. Defective engine controller 20-808 D155AX-5...
Page 201 1. Machine can be operated normally 10 • Starting switch C signal voltage seconds after started Voltage between CN-4 (2) - chassis ground When starting switch is turned ON: Max. 1 V When starting switch is turned to START position: 20 - 30 V 20-809 D155AX-5...
Page 202 Oil level rises Water temperature rises too high ‡ ‡ ‡ ‡ Abnormal sound is made ‡ ‡ ‡ ‡ Vibration is too high Trouble- G-1 G-2 G-3 G-4 G-5 G-6 G-7 G-8 G-9 G-10 G-11 shooting code 20-810 D155AX-5...
Page 203 See volume of engine See volume of engine ‡ ‡ ‡ ‡ ‡ ‡ ‡ ‡ G-12 G-13 G-14 G-15 G-16 G-17 G-18 G-19 G-20 G-21 G-22 G-23 G-24 G-25 G-25 G-26 G-26 G-27 G-28 G-29 G-30 G-31 20-811 D155AX-5...
Page 204 TROUBLESHOOTING G MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM G MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM 20-812 D155AX-5...
Page 205 TROUBLESHOOTING G MODE SYSTEM ELECTRICAL CIRCUIT DIAGRAM 20-813 D155AX-5...
Page 206 • Turn starting switch ON. CN-214 (8) - battery replace and chassis ground normal? • 20 - 30 V Defective wiring harness between Repair or CN-214 (8) - (11) or defective replace starting switch G-1. Related electrical circuit diagram 20-814 D155AX-5...
Page 207 TROUBLESHOOTING G-2. [E0402] (Abnormality in engine controller) is displayed ﬂ Go to troubleshooting of error code [E0460]. 20-815 D155AX-5...
Page 208 Between CN-1 (4) – CN-2 (10) 0.24 – 7.0 kΩ 0.24 – 7.0 kΩ Between (2) – (3) Between CN-1 (6) – CN-2 (10) Min. 1MΩ Min. 1MΩ Between (2) – GND Between CN-1 (6) – GND G-3. Related electrical circuit diagram 20-816 D155AX-5...
Page 209 Between CN-1 (4) – CN-2 (10) 0.24 – 7.0 kΩ 0.24 – 7.0 kΩ Between (2) – (3) Between CN-1 (7) – CN-2 (10) Min. 1MΩ Min. 1MΩ Between (2) – GND Between CN-1 (7) – GND G-4. Related electrical circuit diagram 20-817 D155AX-5...
Page 210 CN-1 (female) (12) - CN- CN-E51. E51 (female) (2) Defective engine controller Replace Table 1 Resistance CN-E51 (male) 85 – 210 Ω Between (1) – (2) Min. 1MΩ Between (1) (2) – GND G-5. Related electrical circuit diagram 20-818 D155AX-5...
Page 211 CN-E52. between CN-2 (female) (9) - CN-E52 (female) (2) Replace Defective engine controller Table 1 CN-E52 (male) Resistance 1 – 2 kΩ Between (1) – (2) Min. 1MΩ Between (1) (2) – GND G-6). Related electrical circuit diagram 20-819 D155AX-5...
Page 212 CN-6 (female) CN-6 (female) Resistance 0.4 – 1.1 Ω Between (7) – (8) Between (4) – (10) Between (3) – (9) Min. 1MΩ Between (7) (8) – GND Between (4) (10) – GND Between (3) (9) – GND 20-820 D155AX-5...
Page 213 CN-6 (female) (3) - CN-E33 replace (female) (1) or between CN-6 (female) (9) - CN-E33 (female) (2) Table 2 Resistance CN-E33 (female) 0.4 – 1.1 Ω Between (1) – (2) Min. 1MΩ Between (1) (2) – GND 20-821 D155AX-5...
Page 214 TROUBLESHOOTING G-7 a), b). Related electrical circuit diagram G-7 a), c). Related electrical circuit diagram G-7 a), d). Related electrical circuit diagram 20-822 D155AX-5...
Page 215 CN-7 (female) CN-7 (female) Resistance 0.4 – 1.1 Ω Between (3) – (9) Between (1) – (7) Between (2) – (8) Min. 1MΩ Between (3) (9) – GND Between (1) (7) – GND Between (2) (8) – GND 20-823 D155AX-5...
Page 216 CN-7 (female) (2) - CN-E36 replace (female) (1) or between CN-7 (female) (8) - CN-E36 (female) (2) Table 4 CN-E36 (female) Resistance 0.4 – 1.1 Ω Between (1) – (2) Min. 1MΩ Between (1) (2) – GND 20-824 D155AX-5...
Page 217 TROUBLESHOOTING G-8 a), b). Related electrical circuit diagram G-8 a), c). Related electrical circuit diagram G-8 a), d). Related electrical circuit diagram 20-825 D155AX-5...
Page 218 Repair or • Turn starting switch OFF. in wiring harness between CN7 replace (13) and chassis ground below 1 Ω? • Disconnect CN-7. (female) (5), (13) - chassis ground Defective engine controller Replace G-9. Related electrical circuit diagram 20-826 D155AX-5...
Page 219 • Turn starting switch OFF. Repair or (female) (7) - CN-E31 (female) (1) or • Disconnect CN-6. (7) and (8) 0.4 - 1.1 Ω? replace between CN-6 (female) (8) - CN-E31 (female) (2) Defective engine controller Replace G-10. Related electrical circuit diagram 20-827 D155AX-5...
Page 220 Repair or (female) (4) - CN-E32 (female) (1) or • Disconnect CN-6. (4) and (10) 0.4 - 1.1 Ω? replace between CN-6 (female) (10) - CN- E32 (female) (2) Defective engine controller Replace G-11. Related electrical circuit diagram 20-828 D155AX-5...
Page 221 Is resistance between CN-6 (female) Repair or (female) (3) - CN-E33 (female) (1) or (3) and (9) 0.4 - 1.1 Ω? • Disconnect CN-6. replace between CN-6 (female) (9) - CN-E33 (female) (2) Defective engine controller Replace G-12. Related electrical circuit diagram 20-829 D155AX-5...
Page 222 • Turn starting switch OFF. Repair or (female) (3) - CN-E34 (female) (1) or • Disconnect CN-7. (3) and (9) 0.4 - 1.1 Ω? replace between CN-7 (female) (9) - CN-E34 (female) (2) Defective engine controller Replace G-13. Related electrical circuit diagram 20-830 D155AX-5...
Page 223 • Turn starting switch OFF. Repair or (female) (1) - CN-E35 (female) (1) or (1) and (7) 0.4 - 1.1 Ω? • Disconnect CN-7. replace between CN-7 (female) (7) - CN-E35 (female) (2) Defective engine controller Replace G-14. Related electrical circuit diagram 20-831 D155AX-5...
Page 224 • Turn starting switch OFF. Repair or (female) (2) - CN-E36 (female) (1) or • Disconnect CN-7. (2) and (8) 0.4 - 1.1 Ω? replace between CN-7 (female) (8) - CN-E36 (female) (2) Defective engine controller Replace G-15. Related electrical circuit diagram 20-832 D155AX-5...
Page 225 Resistance 2.3 – 5.3 Ω 2.3 – 5.3 Ω Between (1) – (2) Between (10) – (11) Between (1), (2) - Between (10), (11) - Min. 1MΩ Min. 1MΩ chassis ground chassis ground G-16. Related electrical circuit diagram 20-833 D155AX-5...
Page 226 CN-7 (female) (11) - CN- E41 (female) (2) Defective engine controller Replace Table 1 CN-7 (male) Resistance 2.3 – 5.3 Ω Between (10) – (11) Between (11) - Min. 1MΩ chassis ground G-17. Related electrical circuit diagram 20-834 D155AX-5...
Page 227 CN-7 (male) 2.3 – 5.3 Ω 2.3 – 5.3 Ω Between (1) – (2) Between (4) – (12) Between (1), (2) - Between (4), (12) - Min. 1MΩ Min. 1MΩ chassis ground chassis ground G-18. Related electrical circuit diagram 20-835 D155AX-5...
Page 228 CN-7 (female) (12) - CN- E42 (female) (2) Defective engine controller Replace Table 1 CN-7 (male) Resistance 2.3 – 5.3 Ω Between (4) – (12) Between (12) - Min. 1MΩ chassis ground G-19. Related electrical circuit diagram 20-836 D155AX-5...
Page 229 (female) (3) - CN-E54 (female) (2) Repair Defective boost pressure sensor Table 3 Resistance CN-1 and CN-E35 (female) Max. 1 Ω Between CN-1 (3) - CN-E54 (2) Max. 1MΩ CN-1 (3) and chassis ground G-20. Related electrical circuit diagram 20-837 D155AX-5...
Page 230 (female) (1) - CN-E53 (female) (2) Defective common rail fuel Repair pressure sensor Table 1 CN-1, CN-E53 (female) Resistance Max. 1 Ω Between CN-1 (1) – CN-E53 (2) Max 1MΩ CN-1 (1) and chassis ground G-21. Related electrical circuit diagram 20-838 D155AX-5...
Page 231 (4) and chassis ground above 1 MΩ? (female) (4) - CN-P7 (female) (1) CN-P7. Defective engine controller Replace Table 1 CN-P7 (male) Resistance 90 k – 3.5 kΩ Between (1) – (2) Between (1) - Min. 1MΩ chassis ground G-22. Related electrical circuit diagram 20-839 D155AX-5...
Page 232 (3) and chassis ground above 1 MΩ? CN-P31. (female) (3) - CN-P31 (female) (1) Replace Defective engine controller Table 1 CN-P31 (male) Resistance 9 k – 0.3 kΩ Between (1) – (2) Between (1) - Min. 1MΩ chassis ground G-23. Related electrical circuit diagram 20-840 D155AX-5...
Page 233 TROUBLESHOOTING G-24 G-24. [E0480] (Abnormality in common rail fuel pressure system) is displayed ﬂ Go to error code [E0481] and [E0482]. 20-841 D155AX-5...
Page 234 [E0474]? Repair or Defective electrical system of replace common rail fuel pressure sensor Defective mechanical system of Is overflow pipe clogging? Replace common rail fuel pressure sensor Repair or Clogging of overflow pipe replace 20-842 D155AX-5...
Page 235 Defective common rail fuel Replace pressure sensor Is any trouble in electrical system detected by troubleshooting of error codes [E0468], Defective fuel supply pump Replace [E0469], [E0470], and [E0471]? Defective electrical system of fuel Repair or supply pump PCV replace 20-843 D155AX-5...
Page 236 3) Start the engine, stall the engine at each speed, and measure the spill fuel amount for 1 minute. Limits for fuel spill amount (total for 6 cylinders) Stall speed (rpm) Spill limit (cc/min) 1,600 1,700 1,800 1,900 2.000 20-844 D155AX-5...
Page 237 CN-4 Engine Resistance CN-P9 Engine Resistance Between CN-P9 Stopped Max. 1 V Stopped Max. 1 Ω Between (6) – (switch) - chassis chassis ground Above 600 rpm 20 – 30 V Above 1,300 rpm Min. 1 MΩ ground 20-845 D155AX-5...
Page 238 TROUBLESHOOTING G-27 G-27. Related electrical circuit diagram 20-846 D155AX-5...
Page 239 Replace • Insert T-adapter in CN- (contact side) chassis ground 20 - 30 V? CPR. Disconnection, defective contact, or short circuit with chassis ground in Repair or wiring harness between CN-7 replace (female) (6), (14) - CN-CPR (female) 20-847 D155AX-5...
Page 240 TROUBLESHOOTING G-28 G-28. Related electrical circuit diagram 20-848 D155AX-5...
Page 241 • Disconnect CN-CPR. Replace (contact side) (5), (13) below 8 V? • Insert T-adapter in CN-7. Short circuit with power source in Repair or wiring harness between CN-7 replace (female) (6) (14) - CN-CPR (female) G-29. Related electrical circuit diagram 20-849 D155AX-5...
Page 242 TROUBLESHOOTING G-30 G-30. [E0490] (Abnormality in Q regulator switch signal) is displayed Caution Remedy Are both of Q regulator switches 1 Defective engine controller Replace and 2 set to "F"? Defective setting of Q regulator Readjust 20-850 D155AX-5...
Page 243 C and chassis ground Replace • Turn starting switch ON. below 1 V? Short circuit with power source in Repair or wiring harness between CN-4 replace (female) (2) - starting switch terminal C G-31. Related electrical circuit diagram 20-851 D155AX-5...
Page 244 TROUBLESHOOTING 20-852 (Blank page) D155AX-5...
Page 245 ﬂ Before carrying out troubleshooting, check that all the related connectors are properly inserted. ﬂ Always connect any disconnected connectors before going on the next step. 20-901 D155AX-5...
Page 246 CN-S51 (13) - oil pressure sensor CN-HHP (2) 3. Disconnection, defective contact, or short circuit with chassis pressure ground in wiring harness between CN-ST3 (2) oil pressure sensor system sensor CN-HHP (3) 4. Defective HSS controller 20-902 D155AX-5...
Page 247 1. If machine is steered when work equipment is relieved, engine 1. Calculates with work equipment oil pressure at 0. may stall. 2. Cannot limit inclination angle of HSS pump when work equip- 2. Only travel and steering operations can be executed normally. ment is relieved. 20-903 D155AX-5...
Page 248 When steering system is turned to right end: potentiometer 0.73 - 0.89 V potentiometer CN-STR (3) system 1 3. Disconnection or defective contact in wiring harness between controller CN-ST2 (9) - potentiometer CN-STR (1) 4. Defective HSS controller 20-904 D155AX-5...
Page 249 2. Flashes warning lamp and sounds warning buzzer. 2. Machine cannot be steered once it is stopped. 1. Controls with signal of steering potentiometer system 2. 1. Machine can be driven and steered normally. 2. Flashes warning lamp and sounds warning buzzer. 20-905 D155AX-5...
Page 250 CN-ST1 (13) - oil pressure sensor CN-ST2 (2) or left side): 3.95 - 4.60 V sensor B 3. Disconnection, defective contact, or short circuit with chassis system ground in wiring harness between controller CN-ST3 (9) - oil pressure sensor CN-ST2 (3) 4. Defective HSS controller 20-906 D155AX-5...
Page 251 1. If machine is steered under heavy load, engine may stall. 2. Cannot limit inclination angle of HSS pump when steering cir- 2. Machine is steered normally under light load. cuit pressure is high or steering circuit is relieved. 3. Flashes warning lamp and sounds warning buzzer. 20-907 D155AX-5...
Page 252 CN-ST3 (4) - speed sensor CN-E07 (1) - (12): 500 - 1,000 Ω E0930 speed sensor 4. Disconnection, defective contact, or short circuit with chassis system ground in wiring harness between controller CN-ST3 (12) - speed sensor CN-E07 (2) 5. Defective HSS controller 20-908 D155AX-5...
Page 253 2. Cannot control inclination angle of HSS pump when engine 2. If machine is steered frequently while traveling down slope, speed is high. durability of HSS motor may be lowered. 3. Neutral position of steering cannot be adjusted. 20-909 D155AX-5...
Page 254 TROUBLESHOOTING ELECTRICAL CIRCUIT DIAGRAM FOR E MODE ELECTRICAL CIRCUIT DIAGRAM FOR E MODE HSS control system 20-910 D155AX-5...
Page 255 TROUBLESHOOTING ELECTRICAL CIRCUIT DIAGRAM FOR E MODE Engine starting system Blade pitch solenoid and ripper pin puller solenoid system 20-911 D155AX-5...
Page 256 • 20 - 30 V Defective fuse, or disconnection or Repair or defective contact in wiring harness replace between outlet of fuse 5 - CN-ST1 (female) (8), (18) E-1. Related electrical circuit diagram 20-912 D155AX-5...
Page 257 Is voltage between CN-STR (1) and Repair or wiring harness between CN-STR (4) - • Turn starting switch ON. replace (4) normal? CN-ST2 (10) • 4.5 - 5.5 V Restart and check that error does not occur. E-2. Related electrical circuit diagram 20-913 D155AX-5...
Page 258 Is voltage between CN-ST1 (13) and neutral position Defective HSS controller • Turn starting switch ON. (9), (19) normal? of steering • 17 - 30 V system) Restart and check that error does not occur. E-3. Related electrical circuit diagram 20-914 D155AX-5...
Page 259 Note 2: Since the machine does not deviate, it can be used as it is for the present. Replace the HSS controller, however, at the earliest chance as a permanent action. (After replacing the control- ler, be sure to "Adjust the neutral position of the steering system".) 20-915 D155AX-5...
Page 260 Table Location Between ST2 (13) – GND Between ST2 (14) – GND Max 1Ω Min. 100 Ω Min. 100 Ω Min. 100 Ω Min. 100 Ω Max 1Ω E-5. Related electrical circuit diagram 20-916 D155AX-5...
Page 261 Voltage Between (1) – (2) In neutral Max. 3.5 V 0.3 – 5.7 kΩ Between CN-ST3 (10) – CN-ST2 (9) Reverse 3.5 – 4.4 V Between (2) – (3) 4 – 6 kΩ E-6. Related electrical circuit diagram 20-917 D155AX-5...
Page 262 Table 2 CN-RSS (male) Resistance Lever position Voltage NEUTRAL Max. 3.5 V Between (1) – (2) 0.3 – 5.7 kΩ Between CN-ST3 (10) – CN-ST2 (9) REVERSE Between (2) – (3) 3.5 – 4.4 V 4 – 6 kΩ 20-918 D155AX-5...
Page 263 TROUBLESHOOTING E-7. Related electrical circuit diagram 20-919 D155AX-5...
Page 264 Transmission F-N Between CN-6 (1) - chassis ground 18 – 30 V Max. 3 V signal Transmission R-N Between CN-6 (5) - chassis ground 18 – 30 V Max. 3 V signal E-8. Related electrical circuit diagram 20-920 D155AX-5...
Page 265 Table 1 Table 2 Forward/Reverse Forward/Reverse CN-ST2 Voltage CN-251 (male) Resistance In neutral 20 – 30 V In neutral Min. 1 MΩ Between (7) – Between (1) – chassis (3) chassis Reverse Reverse Max. 1 V Max. 1 Ω 20-921 D155AX-5...
Page 266 TROUBLESHOOTING E-9. Related electrical circuit diagram 20-922 D155AX-5...
Page 267 Defective work equipment circuit oil Replace pressure sensor Table Work equipment Voltage CN-ST3, CN-ST2 circuit In neutral 0.9 – 1.2 V Between CN-ST3 (2) – CN-ST2 (9) When relieved 2.45 – 2.90 V E-10. Related electrical circuit diagram 20-923 D155AX-5...
Page 268 Defective work equipment circuit oil Replace pressure sensor Table Work equipment Voltage CN-ST3, CN-ST2 circuit In neutral 0.9 – 1.2 V Between CN-ST3 (2) – CN-ST2 (9) When relieved 2.45 – 2.90 V E-11. Related electrical circuit diagram 20-924 D155AX-5...
Page 269 (female) and chassis ground wiring harness between CN-ST1 (female) • Disconnect CN-ST1. replace (11) - CN-014 (female) (1) • 200 - 400 Ω normal? Replace (Adjust Defective HSS neutral position of steering controller system) E-12. Related electrical circuit diagram 20-925 D155AX-5...
Page 270 • Disconnect CN-014 and CN-ST1. resistance between CN-ST1 (female) (11) replace (11) - CN-014 (female) (1) • Min. 1 MΩ and chassis ground normal? Replace (Adjust neutral position Defective HSS controller of steering system) E-13. Related electrical circuit diagram 20-926 D155AX-5...
Page 271 2.4 – 2.6 V 4.1 – 4.3 V 0.73 – 0.89 V Between (19) – (9) 2.4 – 2.6 V 0.6 – 1.1 V 3.9 – 4.4 V Between (20) – (9) E-14. Related electrical circuit diagram 20-927 D155AX-5...
Page 272 1) Measure voltage (V1) between CN-ST2 (19) and (9) and voltage (V2) between CN-ST2 (20) and (9). 2) Add up 2 voltages (V1 and V2) to obtain the sum (V ﬂ The joystick does not move while the voltage is being measured. E-15. Related electrical circuit diagram 20-928 D155AX-5...
Page 273 Are voltage between CN-ST2 (19) and (9) and that between (20) and Turn starting switch ON. Replace • Defective steering potentiometer (9) as shown in table? Go to troubleshooting of displayed error code E-16. Related electrical circuit diagram 20-929 D155AX-5...
Page 274 Between (2) – (4) 4.1 – 4.3 V 0.73 – 0.89 V 5.0 – 8.0 Ω Between (19) – (9) 2.4 – 2.6 V Between (3) – (4) 5.0 – 8.0 Ω E-17. Related electrical circuit diagram 20-930 D155AX-5...
Page 275 Between (2) – (4) 4.1 – 4.3 V 0.73 – 0.89 V 5.0 – 8.0 Ω Between (19) – (9) 2.4 – 2.6 V Between (3) – (4) 5.0 – 8.0 Ω E-18. Related electrical circuit diagram 20-931 D155AX-5...
Page 276 Between (2) – (4) 0.6 – 1.1 V 3.9 – 4.4 V 5.0 – 8.0 Ω Between (20) – (9) 2.4 – 2.6 V Between (3) – (4) 5.0 – 8.0 Ω E-19. Related electrical circuit diagram 20-932 D155AX-5...
Page 277 Between (2) – (4) 0.6 – 1.1 V 3.9 – 4.4 V 5.0 – 8.0 Ω Between (20) – (9) 2.4 – 2.6 V Between (3) – (4) 5.0 – 8.0 Ω E-20. Related electrical circuit diagram 20-933 D155AX-5...
Page 278 1) Measure voltage (V1) between CN-ST2 (19) and (9) and voltage (V2) between CN-ST2 (20) and (9). 2) Add up 2 voltages (V1 and V2) to obtain the sum (V ﬂ The joystick does not move while the voltage is being measured. E-21. Related electrical circuit diagram 20-934 D155AX-5...
Page 279 CN-ST3 replace (female) (1) - CN-ST1 (female) (3) Table Steering Voltage CN-ST3, CN-ST2 In neutral 0.9 – 1.5 V Between CN-ST3 (1) – CN-ST2 (9) When relieved 0.39 – 4.60 V E-22. Related electrical circuit diagram 20-935 D155AX-5...
Page 280 CN-ST2 (female) replace (9) - CN-ST1 (female) (1) Table Voltage CN-ST3, CN-ST2 Steering In neutral 0.9 – 1.5 V Between CN-ST3 (1) – CN-ST2 (9) When relieved 3.95 – 4.60 V E-23. Related electrical circuit diagram 20-936 D155AX-5...
Page 281 CN-ST3 (female) replace (9) - CN-ST2 (female) (3) Table Steering Voltage CN-ST3, CN-ST2 In neutral 0.9 – 1.5 V Between CN-ST3 (9) – CN-ST2 (9) When relieved 3.95 – 4.60 V E-24. Related electrical circuit diagram 20-937 D155AX-5...
Page 282 CN-ST2 (female) replace (9) - CN-ST2 (female) (1) Table CN-ST3, CN-ST2 Steering Voltage In neutral 0.9 – 1.5 V Between CN-ST3 (9) – CN-ST2 (9) When relieved 3.95 – 4.60 V E-25. Related electrical circuit diagram 20-938 D155AX-5...
Page 283 (15) - CN-PUPA (female) (2) • Min. 1 MΩ Repair or Defective HSS controller replace Table CN-PUPA (male) Resistance 10 – 20 Ω Between (1) – (2) Min. 1 MΩ Between (1) – chassis E-26. Related electrical circuit diagram 20-939 D155AX-5...
Page 284 Replace (Adjust neutral position Defective HSS controller of steering system) Table CN-PUPA (male) Resistance 10 – 20 Ω Between (1) – (2) Min. 1 MΩ Between (1) – chassis E-27. Related electrical circuit diagram 20-940 D155AX-5...
Page 285 Replace (Adjust neutral position Defective HSS controller of steering system) Table CN-PUPB (male) Resistance 10 – 20 Ω Between (1) – (2) Min. 1 MΩ Between (1) – chassis E-28. Related electrical circuit diagram 20-941 D155AX-5...
Page 286 Replace (Adjust neutral position Defective HSS controller of steering system) Table CN-PUPB (male) Resistance 10 – 20 Ω Between (1) – (2) Min. 1 MΩ Between (1) – chassis E-29. Related electrical circuit diagram 20-942 D155AX-5...
Page 287 • Disconnect CN-ST3 and CN-E07. replace (4) - CN-E7 (female) (1) and chassis ground normal? • Min. 1 MΩ Disconnection or defective contact in Repair or wiring harness between CN-ST3 (female) replace (12) - CN-E07 (female) (2) E-30. Related electrical circuit diagram 20-943 D155AX-5...
Page 288 Repair or (female) (5) and CN-244 (female) (2) wiring harness between CN-041 (female) • Disconnect CN-014 and CN-244. replace (5) - CN-244 (female) (2) normal? • Max. 1 Ω Defective backup alarm Replace E-31. Related electrical circuit diagram 20-944 D155AX-5...
Page 289 Blade tilt does not work (Solenoid is not turned off) Cause Remedy Short circuit with power source in wiring Repair or When CN-P01 is disconnected, does Start engine. • harness between CN-P01 (female) (2) - replace system become normal? CN-454 (female) (1) Replace Defective blade pitch switch 20-945 D155AX-5...
Page 290 TROUBLESHOOTING E-32 E-32. Related electrical circuit diagram 20-946 D155AX-5...
Page 291 Cause Remedy Short circuit with power source in wiring Repair or When CN-263 is disconnected, does Start engine. harness between CN-263 (female) (2) - • replace system become normal? CN-246 (female) (1) Defective ripper pin puller switch Replace 20-947 D155AX-5...
Page 292 TROUBLESHOOTING E-33 E-33. Related electrical circuit diagram 20-948 D155AX-5...
Page 293 • Turn starting switch ON. voltage between CN-M2 (2) and replace CN-E22 or between CN-M2 (female) (2) - • Max. 1 V chassis ground normal? CN-220 (female) (2) Replace Defective diode (CN-220) See next See next page A page B 20-949 D155AX-5...
Page 294 Defective starting switch Replace • Turn starting switch ON. terminals B and BR normal? • Max. 1 Ω Disconnection or defective contact Repair or in wiring harness between starting replace switch terminal B (CN-260) - fuse 10 - CN-H 20-950 D155AX-5...
Page 295 TROUBLESHOOTING E-34 E-34. Related electrical circuit diagram 20-951 D155AX-5...
Page 296 TROUBLESHOOTING 20-952 (Blank page) D155AX-5...

Komatsu D155AX-5 Shop Manual

Quick Links

Need help?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Komatsu D155AX-5

Summary of Contents for Komatsu D155AX-5