Ignition Control Module: Testing and Inspection

NOTE: Perform an input test for the Ignition Control Module (ICM) only after finishing the fundamental tests for the ignition system and the fuel and emissions system.

HINT: For a quick test of ICM operation, verify that the tachometer operates normally.

1. Remove the distributor cap, the distributor rotor, and the inner cover.

Ignition Control Module:

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 chassis 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 chassis ground. There should be battery voltage.

- If there is no battery voltage, check the Ignition coil and
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 Engine Control Module (ECM) and the ICM.

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

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