Ignition Control Module: Testing and Inspection
Ignition Control Module (ICM) Input TestNOTE:
- Perform an input test for the ignition control module (ICM) after finishing the fundamental tests for the ignition system and the fuel and emissions systems.
1. Remove the distributor cap, the distributor rotor, and the leak cover.
2. Disconnect the wires from the ICM.
3. Turn the ignition switch ON (II). Check for voltage between the BLK/YEL wire and body ground. There should be battery voltage.
- If there is no battery voltage, check the BLK/YEL wire between the ignition switch and the ICM.
- If there is battery voltage, go to step 4.
4. Turn the ignition switch ON (II). Check for voltage between the WHT/BLU wire and body ground. There should be battery voltage.
- If there is no battery voltage, check:
- ignition coil.
- WHT/BLU wire between the ICM and ignition coil.
- If there is battery voltage, go to step 5.
5. Disconnect the ECM/PCM connector B(25P). Check for continuity on the YEL/GRN wire between the ICM and ECM/PCM. There should be continuity.
6. Check for continuity on the YEL/GRN wire to body ground. There should be no continuity.
7. Reconnect the ECM/PCM connector.
8. If all the tests are normal, replace the ICM.