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3.4L & 3.8L

  1. Check instrument cluster. See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. If instrument panel is okay, go to next step.
  2. Turn ignition off. Disconnect PCM harness connectors. Turn ignition on. Using DVOM, measure voltage between affected PCM output circuit and ground. See appropriate SYSTEM WIRING DIAGRAMS article. If battery voltage exists, go to next step. If battery voltage does not exist, go to step  6.
  3. Set DVOM to 10-amp scale. Using DVOM, measure current between affected PCM output circuit and ground. See appropriate SYSTEM WIRING DIAGRAMS article. Monitor reading for about 2 minutes. If current reading remains.05-1.5 amps, go to step  11. If current reading does not remain.05-1.5 amps, go to next step.
  4. Turn ignition off. Disconnect instrument cluster harness connectors. Leave PCM connectors disconnected. Using DVOM, measure voltage between affected PCM output circuit and ground. See appropriate SYSTEM WIRING DIAGRAMS article. If voltage is zero volts, go to step  14. If voltage is present, go to next step.
  5. Locate and repair short to voltage in affected PCM output circuit. After repairs, go to step  16.
  6. Check ignition feed fuse for instrument cluster indicator lights. If fuse is blown, go to next step. If fuse is okay, go to step  8.
  7. Locate and repair short to ground in ignition feed circuit for instrument cluster indicator lights. Replace fuse. After repairs, go to step  16.
  8. Disconnect instrument cluster connectors. Turn ignition on. Using DVOM, measure voltage between ignition feed circuit for instrument cluster indicator lights and ground. If battery voltage exists, go to next step. If battery voltage does not exist, go to step  13.
  9. Check for an open or short to ground in affected PCM output circuit. If problem exists, repair as necessary and go to step  16. If problem does not exist, go to next step.
  10. Check affected PCM output circuit and ignition feed circuit for poor connection at instrument cluster and PCM. If problem exists, repair as necessary and go to step  16. If problem does not exist, go to step  14.
  11. Turn ignition off. Reconnect PCM harness connectors. Disconnect instrument cluster connectors. Turn ignition on. Connect a test light between affected PCM output circuit and ignition feed circuit at instrument cluster harness connector. Using scan tool, perform OUTPUT TESTS function to cycle affected warning light on and off. If test light flashes on and off, check for shorted component or circuit in the output driver circuit. Check for faulty instrument cluster. If test light does not flash on and off, go to next step.
  12. Check affected PCM output circuit for poor connection to PCM. If problem exists, repair as necessary and go to step  16. If problem does not exist, go to step  15.
  13. Locate and repair open in ignition feed circuit to instrument cluster indicator lights. After repairs, go to step  16.
  14. Repair or replace instrument cluster as necessary. After repairs, go to step  16.
  15. Replace PCM. After repairs, go to next step.
  16. Using scan tool, operate affected warning light. If warning light operates properly, system is okay. If warning light does not operate properly, go to step  1.
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