Perkins 1106D Troubleshooting Manual page 190

190
Troubleshooting Section
Note: Shorting a shared supply will affect the status
of three injectors. Ignore the status of the other
injectors that are on the shared shared supply.
Results:
•
OK – The ECM is OK.
Repair: If three injectors that share a supply
indicate "Open", the open circuit is probably
caused by a faulty ECM.
Repair the engine harness or replace the engine
harness, as required.
Verify that the repair eliminates the fault.
STOP.
•
Not OK – There may be a fault with the ECM.
Repair: Temporarily connect a test ECM.
Remove the jumper wire from connector P2 and
reinstall the injector wires.
Perform the "Injector Solenoid Test".
If the test ECM fixes the fault, reconnect the
suspect ECM.
If the fault returns with the suspect ECM, replace
the ECM.
Verify that the repair eliminates the fault.
STOP.
Test Step 8. Check the Harness between
the ECM and the Valve Cover Base for a
Short Circuit
Electrical shock hazard. The electronic unit injec-
tor system uses 67-73 volts.
A. Turn the keyswitch to the OFF position. A strong
electrical shock hazard is present if the keyswitch
is not turned OFF.
B. Disconnect the connectors from the valve cover
base.
C. Turn the keyswitch to the ON position.
D. Perform the "Injector Solenoid Test" at least two
times.
Expected Result:
All cylinders indicate "Open".
Results:
•
OK – All cylinders indicate "Open". Proceed to
Test Step 10.
•
Not OK – One or more cylinders indicate "Short".
Note the cylinders that indicate "Short". Proceed
to Test Step 9.
Test Step 9. Check the ECM for a Short
Circuit
Electrical shock hazard. The electronic unit injec-
tor system uses 67-73 volts.
A. Turn the keyswitch to the OFF position. A strong
electrical shock hazard is present if the keyswitch
is not turned OFF.
B. Disconnect connector P2 from the ECM and check
for evidence of moisture entry.
C. Turn the keyswitch to the ON position.
D. Perform the "Injector Solenoid Test" at least two
times.
Expected Result:
All cylinders indicate "Open" when connector P2 is
disconnected from the ECM.
Note: When the engine harness is disconnected,
all of the diagnostic codes for supply voltage to the
sensors will be active. This is normal. Clear all of
these diagnostic codes after completing this test step.
Results:
•
OK – The short circuit is in the engine harness.
Repair: The fault is most likely in one of the wires
to the injector. Inspect the connectors for moisture
and for corrosion. Also, check the wire insulation
for damage and for strands that are exposed.
Repair the engine harness or replace the engine
harness, as required. Clear all diagnostic codes
after completing this test step.
Verify that the repair eliminates the fault.
STOP.
SENR9982