Part 2 of 2

Chart A-3 Part 2 Of 2:

Chart A-3 Wiring Diagram:

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.


5. Checks for 12 volt supply to injectors.

6. This test will determine if the distributor module is not generating the reference pulse or if the wiring or ECM are at fault. By touching CKT 430 with a test light a reference signal is being generated. If the test light (J-34730-2) blinks at the injector, then the Electronic Control Module (ECM) and wiring is OK.

7. Each time the test light touches CKT 430, the ECM should turn "ON" the fuel pump for 2 seconds.

8. All checks made to this point would indicate that the ECM is at fault. However, there is a possibility of CKT 467 or 468 being shorted to a voltage source either in the engine harness or in the injector harness.

To test for this condition:

- Disconnect the injector 4 way connector.

- Ignition "ON".

- Probe CKTs 467 and 468 on the ECM side of the harness with a test light connected to ground. There should be no light.

- If OK, check the resistance of the injector harness between terminals "A" & "C" "A" & "D" "B" & "D" "B" & "C".

- Should be more than 4 ohms.

- If less than 4 ohms check harness for shorted together and check each injector resistance.

- Resistance should be more 10 ohms.

- If all OK, replace ECM.