Zontes ZT125T-D Maintenance Manual page 8

12. Crankshaft position sensor ........................................................................................................................................ 104
The engine cannot start and there is no sign of fault diagnosis process ................................................................................ 105
The engine cannot be started and there is a car symptom fault diagnosis process ............................................................... 105
Poor acceleration .................................................................................................................................................................... 106
High idling speed of hot car .................................................................................................................................................... 106
Unsteady idle speed of cooling car ......................................................................................................................................... 106
Unsteady idling, easy to cutoff ............................................................................................................................................... 107
Analysis flow chart of EFI failure indicator light always on ..................................................................................................... 108
Electrical schematic diagram of EFI system ............................................................................................................................ 109
4. Ignition system ............................................................................................................................................................................ 110
Know Before Service ............................................................................................................................................................... 110
Troubleshooting ...................................................................................................................................................................... 111
Ignition system layout ............................................................................................................................................................. 112
Electrical schematic diagram of ignition system ..................................................................................................................... 112
Ignition system inspection ...................................................................................................................................................... 113
Ignition timing ......................................................................................................................................................................... 113
Ignition coils ............................................................................................................................................................................ 114
5. Starting system ........................................................................................................................................................................... 115
Know Before Service ............................................................................................................................................................... 115
Troubleshooting ...................................................................................................................................................................... 115
1. Starting relay ............................................................................................................................................................... 115
2. Starter motor .............................................................................................................................................................. 116
3. The starter motor runs slowly ..................................................................................................................................... 116
4. The starter motor is working normally, but the engine cannot be started ................................................................ 116
Ignition system layout ............................................................................................................................................................. 116
Starting system electrical schematic diagram ......................................................................................................................... 117
Starter motor .......................................................................................................................................................................... 117
1. Remove the starter motor .......................................................................................................................................... 117
2. Disassemble the starter motor ................................................................................................................................... 118
Examination ............................................................................................................................................................ 119
Starter motor front cover： ............................................................................................................................ 119
Motor back cover： ........................................................................................................................................ 119
Denki： ........................................................................................................................................................... 119
Check the starting relay .......................................................................................................................................................... 120
1. Operation check .......................................................................................................................................................... 120
2. Check the relay coil ..................................................................................................................................................... 120
2.1 Input line ........................................................................................................................................................... 120
2.2 Ground wire ...................................................................................................................................................... 120
3. Check the starting relay .............................................................................................................................................. 120
4. Disassembly and assembly of the starting relay ......................................................................................................... 120
6. Fuel supply system ...................................................................................................................................................................... 121
Know Before Service ............................................................................................................................................................... 121
Fuel tank removal ................................................................................................................................................................... 121
1. Disassemble the fuel tank assembly ........................................................................................................................... 121
2. Disassemble the fuel pump ......................................................................................................................................... 122
4. Remove the external parts of the fuel tank assembly. ............................................................................................... 123
Examination ............................................................................................................................................................................ 123
1. Fuel pressure test ........................................................................................................................................................ 123
2. Fuel pump inspection .................................................................................................................................................. 123
3. Oil level sensor ............................................................................................................................................................ 123
7. Cooling system ............................................................................................................................................................................ 124
Know Before Service ............................................................................................................................................................... 124
Troubleshooting ...................................................................................................................................................................... 124
1. The engine temperature is too high:........................................................................................................................... 124
2. The engine temperature is too low: ............................................................................................................................ 124
3. Coolant leakage ........................................................................................................................................................... 124
Coolant system distribution map ............................................................................................................................................ 125
D350 ................................................................................................................................................................................ 125
D125 ................................................................................................................................................................................ 125
Coolant flow diagram .............................................................................................................................................................. 126
D350 ................................................................................................................................................................................ 126
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