Chart A-4 Injector Circuit Diagnosis

Chart A-4:

A-3 Circuit:

CIRCUIT DESCRIPTION:
This chart should only be used if diagnosis in Chart A-3 indicated an injector circuit problem.

CHART TEST DESCRIPTION:
Number(s) below refer to circled number(s) on the diagnostic chart:
1. This test will determine if the ignition control module is generating a reference pulse or the wiring is at fault or if the Powertrain Control Module (PCM) 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 PCM 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 PCM side of the circuit.
3. This test checks for continuity to the PCM.

DIAGNOSTIC AIDS:
The PCM has integrated IC circuits that are fault protected, therefore, if a circuit has failed, the integrated IC may not be damaged and will keep the circuit open until the fault in the circuit has been corrected. When the fault has been corrected, reinstall PCM and check circuit. Replace PCM only if the circuit is still inoperative.