Part 2 of 3

Chart A-3 Part 2 Of 3:

Chart A-3 Wiring Diagram:

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

1. Checks for 12 volts supply to injectors. Due to the injectors wired in parallel, there should be a light "ON" on both terminals.

2. Checks continuity of CKT 467 and 468.

3. All checks made to this point would indicate that the Electronic Control Module (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 harness with a test light connected to ground. There should be no light. If light is "ON", repair short to voltage.

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

^ Should be more than 4 ohms.

^ If less than 4 ohms, check harness for wires shorted together and check each injector resistance. (Resistance should be 8 ohms or more.)

^ If all OK, replace ECM.