Chart A-4 Injector Circuit Diagnosis

Injector Circuit Chart A-4:

Injector Circuit:

Circuit Description:
This chart should only be used if diagnosis in CHART A-3 indicated an injector circuit problem. If both injector circuits fail to blink when tested, diagnose one injector circuit at a time.

Test Description:
Number(s) below refer to circled numbers on the diagnostic chart.

1. This test will determine if the ignition module is generating a reference pulse, if the wiring is at fault or if the ECM is at fault. By touching and removing a test light, connected to 12 volts, to CKT 430, a reference pulse should be generated. If injector test light blinks, the ECM and wiring are OK.

2. This step tests for 12 volts to the injector. It will also determine if there is a short to voltage on the ECM side of the circuit.

3. This test checks for continuity to the ECM.