Note:
- When the malfunction indicator light is on (MIL).
- Proceed to check the ignition control unit input signal (ICM), after performing basic checks of the ignition system, fuel system and emission control system.
Motors DI4A3, DI4A4, DI5Z4, DI5Z5, DI6Y4 and DI6Y9:
1. Disconnect the 7K connector from the distributor.
2. Turn the ignition switch ON (II) and check the voltage between pin No. 7 and the body.
- There should be battery voltage.
- If there is no battery voltage, check for an open in the red wire (RED) or black/yellow wire (BLK/YEL) between the under-panel fuse/relay box and the ICM, or fuse #9 (15A) to burnout.
3. Turn the ignition switch OFF, check the continuity between pin No. 4 and the housing.
- There must be conductivity.
- If there is no continuity, check for a break in black (BLK) wire between the ICM and the housing or poor grounding in G101.
4. Check continuity between pin No. 6 and the tachometer connector.
- There must be conductivity.
- If there is no continuity, check for a break in blue (BLU) wire between the tachometer connector and the ICM.
5. Check the continuity between contact No. 6 of the body.
- There must be conductivity.
- If there is continuity, check for short in blue (BLU) wire between the tachometer connector and the ICM to the housing.
6. Remove the ignition distributor cap (DI), ignition distributor slider (DI) and a protective cap. Check out black and blue (BLK and BLU) wires and check the ignition coil.
7. If the test results are normal, replace the ignition distributor housing assembly (DI).
In addition to DI4A3, DI4A4, DI5Z4, D15Z5, DI6Y4 and D16Y9 engines:
1. Remove the ignition distributor cap (Di) , ignition distributor slider and insulating cover (TES).
2. Disconnect the wires from the ICM.
HITACHI
TEC
3. Turn the ignition switch ON (II). Check the voltage between the BLK/YEL wire and the body.
- Should be battery voltage/
- If there is no battery voltage, check the BLK/YEL wire between the under-panel fuse/relay box and the ICM.
- If there is battery voltage, proceed to step 4.
4. Turn the ignition switch ON (II). Check the voltage between wire *1 and the body.
There must be tension.
- If there is no battery voltage, check:
-Ignition coil.
-Wire *1 between ignition coil and ICM.
- If there is battery voltage, proceed to step 5.
*l: BLU2 wire (HITACHI)
WHT/BLU wire (TES)
5. Check the continuity of the BLU1 wire between the tachometer connector and the ICM. There must be conductivity.
6. Check continuity on wire BLU1 to the body. There must be conductivity.
7. If the test results are normal, replace the ICM.