KENR6933 167
Troubleshooting Section
Test Step 8. Check the Harness between
the ECM and the Va lve Cover Base for a
Short Circuit
Electrical shock hazard. The electronic unit inje c-
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 “Current Below Normal”.
Results:
•
OK – All cylinders indicate “Current Below
Normal”. Proceed to Test Step 10.
•
Not OK – One or more cylinders indicate “Current
Above Normal”. Note the cylinders that indicate
“Current Above Normal”. Proceed to Test Step 9.
Test Step 9. Check the E CM for a Short
Circuit
Electrica
l shock hazard. The electronic unit injec-
tor system uses 67-73 volts.
A. Turn the ke
yswitch 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 th
e “Injector Solenoid Test” at least two
times.
Expected
Result:
All cylinders indicate “Current Below Normal” when
connecto
r P2 is disconnected from the ECM.
Note: When the engine harness is disconnected,
all of the diagn
ostic codes for supply voltage to the
sensors will be active. This is normal. Clear all of the
logged diagnostic codes after completing this test
step.
Results:
•
OK – The short circuit is in the engine harness.
Repair: The fa
ult 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 an
d for strands that are exposed.
Repair the engine harness or replace the engine
harness, as r
equired. Clear all diagnostic codes
after completing this test step.
Use the elect
ronic service tool in order to clear all
logged diagnostic codes and then verify that the
repair eliminates the fault.
STOP.
•
Not OK – Ther
emaybeafaultwiththeECM.
Repair: Temporarily connect a test ECM.
Perform the “Injector Solenoid Test”.
If the test E
CM fixes the fault, reconnect the
suspect ECM.
If the fault
returns with the suspect ECM, replace
the ECM.
Use the ele
ctronic service tool in order to clear all
logged diagnostic codes and then verify that the
repair eliminates the fault.
STOP.
Test Step 1
0. Check the Engine Harness
Under the V
alve Cover 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. Remove the valve cover.
C. Disconnect each of the injectors that indicate a
“Short” from the wiring harness. Ensure that each
of the connectors from the disconnected injector
harness does not touch any other components.
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