Perkins 1106D Troubleshooting Manual page 118

118
Troubleshooting Section
E. If a P1:41 is installed, then temporarily disconnect
the pin. If a P1:42 is installed, then temporarily
disconnect the pin.
F. Reconnect the P1 OEM connector to the ECM.
G. Turn the keyswitch to the ON position.
H. Check for active diagnostic codes on the Perkins
EST.
Note: A "voltage high" diagnostic code (open circuit)
should be active for all of the following sensors:
•
Engine pressure sensors
•
Engine temperature sensors
•
Analog throttle demand sensors (if equipped)
Expected Result:
The 5 volt diagnostic codes are not active. A "voltage
high" diagnostic code (open circuit) is active for all of
the engine pressure sensors, temperature sensors
and throttle demand sensors (if equipped).
Results:
•
OK – The 5 volt diagnostic code is not active.
Repair: Use the Perkins EST in order to clear all
diagnostic codes.
Replace all wires to the original configuration.
Verify that the repair eliminates the fault.
STOP.
•
Not OK – The 5 volt diagnostic codes are still
active.
Repair: Connect a test ECM.
If the test ECM fixes the fault, reconnect the
suspect ECM.
If the fault returns, permanently install the new
ECM.
Verify that the repair eliminates the fault.
STOP.
Test Step 6. Check the +5 Volt Supply
Wire for a Short to Engine Ground or a
Short to Other Wires in the Harness
A. Turn the keyswitch to the OFF position.
B. Disconnect the J2/P2 ECM connector.
C. Ensure that the analog sensors are disconnected
at the sensor connectors.
Note: Wiggle the harness during the following test
procedures in order to identify any intermittent short
connectors.
D. Measure the resistance from P2:2 +5 V supply to
all terminals on the P2:2 ECM connector. Measure
the resistance from the P2:2 to the ECM ground
strap. Measure the resistance from the P2:41 +5
V supply to all terminals on the ECM connector.
Measure the resistance from the P2:41 to the
ECM ground strap.
Expected Result:
Each resistance measurement is more than 20,000
Ohms.
Results:
•
OK – The resistance check does not indicate a
short in the engine harness to engine ground.
Repair: Repeat this process for J1:41, J1:54 and
J1:55 if a throttle sensor is installed. If the throttle
sensors are OK then the fault is intermittent.
Refer to Troubleshooting, "Electrical Connectors
- Inspect".
Use the Perkins EST in order to clear all logged
diagnostic codes.
Replace all wires to the original configuration.
Restart the Test Step.
STOP.
•
Not OK – A resistance measurement is less than
20,000 Ohms. The +5 V supply wire is shorted
in the engine harness or the +5 V supply wire is
shorted to the engine ground.
Repair: Repair the faulty wire or replace the faulty
wire.
Use the Perkins EST in order to clear all logged
diagnostic codes.
Verify that the repair eliminates the fault.
STOP.
SENR9982