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Pcm Output Diagnosis (2.2L): Notes

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in appropriate SELF-DIAGNOSTICS article. After performing OBD system check, go to next step.
  2. Turn ignition on with engine off. Connect scan tool to Data Link connector (DLC). If a No. 1 is displayed below any of the number output drivers, go to next step. If a No. 1 is not displayed below any of the number output drivers, go to step  4.
  3. Disconnect electrical connector from component related to malfunctioning circuit. If a No. 1 is still displayed below corresponding output driver, go to step  6. If a No. 1 is not displayed below any of the number output drivers, go to step  9.
  4. Using scan tool, command output being checked while watching corresponding position for that circuit. If that circuits position does not change to a No. 1, go to next step. If that circuits position changes to a No. 1, go to step  7.
  5. If component or function does not operate when commanded, go to step  9. If component or function operates when commanded, go to step  11.
  6. Turn ignition off. Check for an open, short to voltage or short to ground in any corresponding circuit that indicated a No. 1 below output driver. Repair component or component circuit as necessary and go to step  11. If circuits are okay, go to step  10.
  7. Disconnect electrical connector from component related to malfunctioning circuit. Using scan tool, command output being checked while watching corresponding position for that circuit. If a No. 1 is still displayed below corresponding output driver, go to next step. If a No. 1 is not displayed below any of the number output drivers, go to step  9.
  8. Turn ignition off. Check for an open, short to voltage or short to ground in any corresponding circuit that indicated a No. 1 below output driver. Repair component or component circuit as necessary and go to step  11. If circuits are okay, go to step  10.
  9. Diagnose and repair any component that malfunctioned when commanded with scan tool. After repairs, go to step  11.
  10. Replace PCM. Program replacement PCM using required equipment. After repairs, go to next step.
  11. Start engine and operate vehicle under condition under which original symptom was noted. If system does not operate properly, go to step  2. If system operates properly, go to DIAGNOSTIC AIDS .
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