Ignition Control Module: Testing and Inspection

NOTE: 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. The tachometer should operate normally.

1. Remove the distributor ignition cap, the distributor ignition rotor, and the leak cover.





2. Disconnect the BLK/YEL, WHT/BLU, YEL/GRN, and BLU wires from the ICM.

3. Turn the ignition switch ON. 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. 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 ignition coil and the ICM.
^ If there is battery voltage, go to step 5.

5. Check the YEL/GRN wire between the ECM and the ICM.

6. Check the BLU wire between the tachometer and the ICM.

7. If all tests are normal, replace the ICM.