Ignition Control Module: Testing and Inspection

NOTE:
- If the malfunction indicator lamp (MIL) comes on, refer to the Fuel and Emission System.
- 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 if the ICM is OK.

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

F23A1 and F23A4 2.3L SOHC VTEC:

F23A5 2.3L SOHC Non-VTEC:

2. Disconnect the wires from the ICM (A).
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/BLK (WHT/BLU for the F23A5 engine) wire and body ground. There should be battery voltage.

- If there is no battery voltage, check:
- ignition coil.
- WHT/BLK (WHT/BLU for the F23A5 engine) wire between the ICM and ignition coil.
- If there is battery voltage, go to step 5.

5. Disconnect the 25P connector from the ECM/PCM, and 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. If all the tests are normal, reconnect the ECM/PCM 25P connector B, and replace the ICM.