Code 3: Map Sensor
WARNING: This page is about a different car, the 1994 Acura Legend. However, it is still accessible from the selected car via links, so may be relevant.
- Turn ignition off. Remove ACG fuse (No. 15, 7.5-amp) from underdash fuse box for 10 seconds to reset ECM. Start engine. Connect jumper wire to self-diagnostic connector. Observe MIL. If Code 3 is not present, problem is intermittent. Check for poor or loose connection at MAP sensor and ECM connector. Test drive vehicle and retest.
- If Code 3 is present, turn ignition off. Disconnect 3-pin connector at MAP sensor. Turn ignition on. Measure voltage between Yellow/White wire terminal (+) and body ground. See Fig 1 . If about 5 volts is present, go to step 4). If voltage is not about 5 volts, turn ignition off. Connect connector "D" of ECM Test Harness (07LAJ-PT3010A ) to ECM, leaving vehicle wiring harness disconnected.
- Turn ignition on. Measure voltage between test terminals D17 (+) and D21 (-). If voltage is about 5 volts, repair open in Yellow/White wire between ECM terminal D19 and MAP sensor. If voltage is not about 5 volts, turn ignition off, replace ECM and retest.
- If voltage was about 5 volts in step 2), measure voltage between Yellow/White and Green/White wires at MAP sensor. See Fig 1 . If voltage is not about 5 volts, repair open in Green/White wire between ECM connector terminal D21 and MAP sensor. If voltage is about 5 volts, measure voltage between Red (+) and Green/White (-) wire terminals at MAP sensor.
- If voltage is not about 5 volts, go to step 7). If about 5 volts are present, turn ignition off. Reconnect MAP sensor. Install ECM Test Harness (07LAJ-PT3010A ) to ECM and vehicle wiring harness. See Figure . Turn ignition on.
- Measure voltage between test terminals D17 (+) and D21 (-). If voltage is not about 3 volts, replace MAP sensor. If about 3 volts are present, replace ECM and retest.
- If voltage was not about 5 volts in step 5), turn ignition off. Connect connector "D" of ECM Test Harness (07LAJ-PT3010A ) to ECM, leaving vehicle wiring harness disconnected.
- Turn ignition on. Measure voltage between test terminals D17 (+) and D21 (-). If voltage is about 5 volts, repair open or short in circuit D17 (Red wire) between ECM connector and MAP sensor. If voltage is not about 5 volts, replace ECM and retest.