Perkins 1106D Troubleshooting Manual page 189

SENR9982
E. Insert one end of the jumper wire into the terminal
for the suspect injector's supply. Insert the other
end of the jumper wire into the terminal for the
suspect injector's return circuit.
F. Perform the "Injector Solenoid Test" at least two
times.
G. Repeat this test for each suspect injector. Stop
the "Injector Solenoid Test" before handling the
jumper wires.
Expected Result:
Perkins EST displays "Short" for the cylinder with the
jumper wire.
Results:
•
OK – The harness between the ECM and the
valve cover base is OK. Proceed to Test Step 6.
•
Not OK – There is a fault between the ECM and
the valve cover base. Proceed to Test Step 7.
Test Step 6. Check the Injector Harness
Under the Valve Cover
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 the harness from the suspect injector.
Disconnect the harness from the injectors that
shares the same supply circuit as the suspect
injector.
Note: Injectors 1, 2, and 3 share a common injector
driver circuit in the ECM. Injectors 4, 5, and 6 share
a common injector driver circuit in the ECM. If three
injectors that share a common supply indicate
"Open", the open circuit is probably caused by a
faulty ECM.
D. Thoroughly clean the terminals on three injectors
and on the harness connectors.
E. Exchange the harness between two of the three
injectors that share the common driver.
F. Turn the keyswitch to the ON position.
G. Perform the "Injector Solenoid Test" at least two
times.
Expected Result:
Exchanging the harness between the two injectors
caused the fault to move to the other injector.
Results:
•
OK – There is a fault with the injector harness
under the valve cover.
Repair: Repair the injector harness or replace the
injector harness under the valve cover.
Verify that the repair eliminates the fault.
STOP.
•
Not OK – The injector may be faulty.
Repair: Replace the faulty injector.
Restore the wiring to the correct injectors.
Perform the "Injector Solenoid Test".
Verify that the repair eliminates the fault.
STOP.
Test Step 7. Check the ECM for an Open
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.
C. Remove the supply wire and the return wire for
the suspect injector from connector P2. Install a
jumper wire into connector P2 in order to provide
a short between the supply and the return of the
suspect injector.
D. Reinstall connector P2 to the ECM.
E. Turn the keyswitch to the ON position.
F. Perform the "Injector Solenoid Test" at least two
times.
Expected Result:
Perkins EST displays "Short" for the cylinder with the
jumper wire.
189
Troubleshooting Section