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DTC 0 - Engine Control Module (ECM)

  1. If Malfunction Indicator Light (MIL) never comes on, even for 2 seconds after ignition is turned on, go to next step. If MIL stays on or comes on after 2 seconds, go to step 5).
  2. Turn ignition on. If low oil pressure light is on, go to next step. If low oil pressure light is not on, repair short in Yellow wire between No. 1 BACK-UP LIGHTS, METER LIGHTS (10-amp) fuse and gauge assembly.
  3. Try to start engine. If engine starts go to step 4). If engine does not start, turn ignition off. Connect test harness between ECM and ECM connector. See TEST EQUIPMENT  . Measure voltage between test harness connector terminal A23 and ground, and A24 and ground one at a time. If less than one volt is present on either terminal, substitute a known-good ECM and recheck. If symptom or indication goes away, replace original ECM. If more than one volt is present, repair open in Black wire(s) between ECM connector terminal A23 or A24 and ground (G101) located at left side of intake manifold.
  4. Turn ignition off. Connect test harness between ECM and ECM connector. See TEST EQUIPMENT  . Connect test harness terminal A13 to ground. Turn ignition on. If MIL illuminates, substitute a known-good ECM and recheck. If symptom or indication goes away, replace original ECM. If MIL does not illuminate, replace MIL bulb or repair open Light Green/Red wire between ECM connector terminal A13 and gauge assembly.
  5. Connect SCS Service Connector (07PAZ-0010100) to service check connector. Turn ignition on. If Malfunction Indicator Light (MIL) indicates a DTC, go to DIAGNOSTIC TROUBLE CODE IDENTIFICATION  . After identifying DTC, go to appropriate testing in DIAGNOSTIC TROUBLE CODES. If MIL does not indicate a DTC, go to next step.
  6. Remove SCS service connector from service check connector. Attempt to start engine. If engine starts, go to next step. If engine does not start, go to step 10).
  7. Turn ignition off. Connect test harness between ECM and ECM connector. See TEST EQUIPMENT  . Turn ignition on. Measure voltage between test harness terminal D4 (+) and D22 (-). If approximately 5 volts is present, go to next step. If approximately 5 volts is not present, repair short to ground in Red wire between ECM connector terminal D4 and service check connector.
  8. Connect SCS Service Connector (07PAZ-0010100) to service check connector. Measure voltage between test harness terminals D4 (+) and D22 (-). If approximately 5 volts is not present, go to next step. If approximately 5 volts is present, repair open Red wire between ECM connector terminal D4 and service check connector or repair open Green/Blue wire between ECM connector terminal D22 and service check connector. After repair disconnect SCS service connector. Test drive car and recheck MIL for a DTC.
  9. Remove SCS service connector from service check connector. Turn ignition off. Disconnect ECM connector "A" from ECM. DO NOT disconnect main wiring harness (on vehicle) from test harness. Turn ignition on. If MIL is not on, substitute a known-good ECM and recheck. If symptom or indication goes away, replace original ECM. If MIL is on, repair short to ground in Light Green/Red wire between ECM connector terminal A13 and MIL.
  10. Inspect No. 33 PGM-FI MAIN RELAY (15-amp) fuse located in underhood fuse/relay box. If fuse is okay, go to next step. If fuse is open, replace fuse and repair short in White/Green wire between PGM-FI MAIN RELAY (15-amp) fuse and PGM-FI main relay.
  11. Inspect No. 2 FUEL PUMP (15-amp) fuse in underdash fuse/relay box. If fuse is okay, go to next step. If fuse is open, repair short in Red/White wire between underdash fuse/relay box and PGM-FI main relay.
  12. Turn ignition on. While observing MIL, disconnect 3-pin Manifold Absolute Pressure (MAP) sensor, Throttle Position (TP) sensor and EGR valve lift sensor, each one at a time. If MIL remained on, go to next step. If MIL does not remain on, replace sensor that caused MIL to go out.
  13. Turn ignition off. Connect test harness between ECM and ECM connector. See TEST EQUIPMENT  . Disconnect ECM connector "D" from ECM. DO NOT disconnect main wiring harness (on vehicle) from test harness. Check for continuity between ground and test harness terminals D19 and D20. If continuity is not present, go to next step. If continuity is present, repair short to ground in Yellow/White wire between ECM connector terminal D19 and MAP sensor or repair short to ground in Yellow/Blue wire between ECM connector terminal D20 and TP sensor or EGR valve lift sensor.
  14. Reconnect all sensor connectors. Reconnect ECM connector "D" to ECM. Turn ignition on. Measure voltage between ground and test harness terminal A26. Record voltage reading. Measure voltage between ground and test harness terminal B2. Record voltage reading. If voltage reading for either terminal was less than one volt, substitute a known-good ECM and recheck. If symptom or indication goes away, replace original ECM. If voltage reading for either terminal is more than one volt, repair open in Brown/Black wire between ECM terminals A26 or B2 and ground (G101) located at left side of intake manifold.
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