No Communication With PCM
- Check junction connectors and wiring harness between PCM and DLC and between PCM and power supply. If wiring and connectors are okay, check MFI relay. Refer to RELAYS in the SYSTEM/COMPONENT TESTS - 2.0L TURBO article. If MFI relay is okay, disconnect PCM connector. Turn ignition on. Measure voltage between PCM connector terminal No. 82 (Black/White wire) and ground.
- If battery voltage exists, go to step 4 . If battery voltage does not exist, check junction connector between MFI relay connector and PCM and wiring harness between ignition switch connector and PCM. If wiring and connectors are okay, disconnect ignition switch connector.
- With ignition switch in ACC position, check for continuity between terminals No. 1 and 6. With ignition switch in ON position, check for continuity between terminal No. 1 and 2, 1 and 4, and 1 and 6. With ignition switch in START position, check for continuity between terminal No. 1 and 2, 1 and 3, and 1 and 5. If continuity is not as specified, replace ignition switch.
- Measure voltage between PCM connector terminal No. 38 (Blue/Green wire) and ground. If battery voltage exists, ground terminal No. 38 (Blue/Green wire) and measure voltage between PCM connector terminals No. 12 (Black/Red wire), No 25 (Black/Red wire), and ground. If battery voltage exists, go to next step. If battery voltage does not exist, check MFI relay connector and PCM and wiring harness between MFI relay connector and PCM.
- Check continuity between PCM connector terminals No. 13 (Black wire), No. 26 (Black wire) and ground. If continuity exists, go to next step. If continuity does not exist, check wiring harness between PCM and ground.
- Measure voltage between PCM connector terminal No. 80 (Red/Blue wire) and ground. If battery voltage exists, check PCM connector. If PCM connector is okay, replace PCM. If battery voltage does not exist, check wiring harness between PCM and battery.