Operation CHARM: Car repair manuals for everyone.

NB7 - Check ICM



- Key "OFF".

- Breakout box installed.

- Connect Powertrain Control Module (PCM) to breakout box.

- Reconnect Ignition Control Module (ICM).

- Connect Digital Volt/Ohm Meter (DVOM) between test pin 4 and test pin 16 at the breakout box and between:

FEDERAL (49 STATE) MODELS

- Test pin 32 and test pin 16 at the breakout box.

CALIFORNIA (SEQUENTIAL FUEL INJECTION) MODELS

- Test pin 31 and test pin 16 at the breakout box.

- Start engine.

- Observe DVOM when voltage is allowed to stabilize.

- Lightly tap on ignition components (to simulate road shock).

- Wiggle both ICM connectors.

- A sudden change in voltage indicates a fault.

- Is a fault indicated?

Yes -- Disconnect and inspect connectors. If connector and terminals are good, remove breakout box, reconnect all components and go to Ignition Systems.

No -- Go to NB8. NB8 - Check EEC Harness