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Ignition Control Module: Testing and Inspection

Ignition Control Module (ICM) Input Test

NOTE:
- See fuel and emissions if the malfunction indicator lamp (MIL) came on.
- 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. Disconnect the 3P connector from the distributor.
2. Turn the ignition switch ON (II). Check for voltage between the No.2 terminal and body ground. There should be battery voltage.
- If there is no battery voltage, check:
- Ignition coil.
- BLK/YEL wire between the ICM and ignition coil.
- If there is battery voltage, go to step 3.

3. Turn the ignition switch ON (II). Check for voltage between the No.3 terminal and body ground. There should be battery voltage.
- If there is no battery voltage, check:
- ignition coil.
- BLU wire between the ICM and ignition coil.
- If there is battery voltage, go to step 4.

4. Disconnect the A (32P)*1 or B (25P)*2 connector from the ECM*1 (PCM)*2, and check for continuity on the No.1 terminal between the ICM and ECM (PCM). There should be continuity.
*1: '97 model, *2: '98 - '99 models
5. Check for continuity on the No.1 terminal to body ground. There should be no continuity. If there is continuity (short to ground), the ICM is probably damaged.
6. Reconnect the ECM (PCM) A (32P) or B (25P) connector and the distributor 3P connector.
7. If all the tests are normal, replace the ICM.