Ignition Control Module: Testing and Inspection

Ignition Circuit:

Measuring Ignitor Supply Voltage:

- Disconnect ignitor connector.
- Turn key on and confirm that battery voltage exists between terminals "IG+" and "IG-".
If no or low voltage exists, check fuse, wiring, ignition coil and connectors.

Injector Connector:

- Disconnect injector connector.
- Check "IGt" terminal voltage according to following.

^ "IGt" Signal Voltage Check Procedure.
- Disconnect ignitor connector.
- Connect analog voltmeter between terminal "IGt" and ground.
- There must be 5 VDC pulsing output when cranking engine.
If there is incorrect voltage, "Or" wire is open, shorted wire or poor connection at ECM "B6" terminal. If wire and connection are good, substitute a known good ignitor and recheck.

- Check "IGf" terminal voltage according to following.

^ "IGf" Signal Voltage Check Procedure.
- Connect analog voltmeter between terminal "IGf" (ECM A18) and ground.
- There must be 0 - 2 VDC or 4 - 5 VDC when ignition is on.
- Voltage should vary during cranking.
If there is correct voltage, "Y/R" wire is open, short to ground or poor connection of ignitor terminal "IGf". If wire and connection are good, substitute a known good ignitor and recheck.