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Check Engine Light On, Led Won't Flash Code

  1. Turn ignition off. Remove and inspect ECU fuse, HAZARD fuse (main fuse block) and fuse No. 14 (underdash fuse block). Inspect ground connections at thermostat housing or Brown/Black and Black/Red wires at connector located on right front strut tower.
  2. Turn ignition on. Verify CHECK ENGINE light stays on for 2 seconds. If light does not stay on for 2 seconds, check for poor connections and loose wires at main relay, ECU fuse or fuse No. 14. If CHECK ENGINE light comes on, check ECU LED inspection light for codes. If codes are present, repair trouble code(s). If no code(s) are present or if LED does not flash, go to next step.
  3. Start engine. If engine does not start, go to step 4). If engine starts, turn ignition off. Disconnect ECU connector "B". Turn ignition on. Verify if CHECK ENGINE light is on. If light is on, repair short to ground in Green/Orange wire between ECU terminal B6 and combination meter. If light does not turn on, substitute a known good ECU, and recheck. If condition is corrected, replace original ECU.
  4. If engine does not start, turn ignition on. Individually disconnect 3-wire connectors at MAP, throttle angle and EGR valve lift (1.5L A/T California) sensors. If CHECK ENGINE light turns off while disconnecting connector from any sensor, replace particular sensor. If light stays on throughout, go to step 5).
  5. Reconnect all sensor connectors. Disconnect 3-wire connector to Atmospheric Pressure (PA) sensor. Check if LED is flashing Code 13. If Code 13 is present, replace PA sensor. If Code 13 is not present, go to step 6).
  6. Turn ignition off. Connect ECU Test Harness (07999-PD6000A ) to ECU main harness side only. See Figure . Check continuity between ground and terminals C13 and C15. See Figure . If continuity is present, repair short in Yellow/Red wire between ECU and MAP sensor or in Yellow/White wire between ECU and PA, throttle angle or EGR valve lift sensor. If continuity is not present, go to step 7).
  7. Reconnect 3-wire PA sensor connector. Connect ECU Test Harness (07999-PD6000A ) connectors "A", "B" and "C" to ECU. See Figure . Turn ignition on. Measure voltage between ground and ECU terminals A16 and A18. See Figure . If less than one volt is present, go to step 8). If more than 1 volt is present, repair open in wire between ECU terminals A16 and A18 and thermostat housing (ground).
  8. Measure voltage between ECU terminals A13, A15 and A18. If battery voltage is present, substitute a known good ECU, and recheck. If condition is corrected, replace original ECU. If battery voltage is not present, repair open in Yellow/Black wire between ECU terminals A13 and A15 and main relay. Check main relay and connectors.
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