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Testing Procedure

To ensure correct diagnosis and repair, testing should be done in the following sequence:

  1. Ensure all customer complaints or observations are recorded. Test drive vehicle with customer when necessary for malfunction verification.
  2. Retrieve and record stored DTCs and 1st trip DTCs. See RETRIEVING CODES . Print or record freeze frame data and erase DTC(s). See CLEARING CODES .
  3. Recreate conditions in which malfunction occurred to reset DTC. If DTC is detected, go to step 5). If malfunction is not detected, consider the following conditions to recreate an intermittent malfunction:
    • Vehicle Vibration Drive vehicle on rough road or with engine vibrating at idle (with A/C on).
    • Heat Or Cold Sensitive Incident occurs on only extremely hot or cold days.
    • Water Intrusion Water may intrude into connectors and cause corrosion between connector terminals.
    • Electrical Load Operate multiple accessories (P/W, P/L, A/C, wipers, lights, etc.).
    • Hot Or Cold Start Start vehicle either hot or cold.
    • Poor Connections

    Wiring harnesses may be checked by gently wiggling wire harness during testing. Relays and sensors may be checked by gently tapping during testing.

    If malfunction is still not detected, go to next step.

    NOTE: Perform DTCs in order of priority. See DTC PRIORITY IDENTIFICATION  table.
  4. Perform malfunction confirmation procedure (if available) at the beginning of each DTC diagnostic test to set appropriate DTC. See appropriate TESTS W/CODES article .
  5. If DTC is set, perform appropriate procedure. If DTC does not reset, diagnose malfunction by symptom. See TESTS W/O CODES article for diagnosis by symptom. After performing necessary repairs, go to next step.
  6. Rerun test situations which set DTC(s). Retrieve codes and confirm DTC P0000 (System Normal) is detected. Clear DTC(s) from PCM and TCM memory. See CLEARING CODES .
DTC PRIORITY IDENTIFICATION

Priority (1) DTC
1 (Low Priority) P0100, P0110, P0115, P0120, P0125, P0180, P0325, P0335, P0340, P0500, P0605, P1320, P1335, P1336, P1400 & P1706
2 (Normal Priority) P0105, P0130, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0139, P0140, P0141, P0150, P0151, P0152, P0153, P0154, P0155, P0443, P0446, P0450, P0510, P0705, P0710, P0720, P0725, P0740, P0744, P0745, P0750, P0755, P1105, P1401, P1444, P1446, P1447, P1448, P1490, P1491, P1492, P1493, P1705 & P1760
3 (High Priority) P0150, P0171, P0172, P0174, P0175, P0300, P0301, P0302, P0303, P0304, P0305,
5 P0306, P0400, P0402, P0420, P0440, P0505, P0600, P0731, P0732, P0734, P1320 & P1440
(1) DTCs do not apply to all models. See appropriate DTC IDENTIFICATION table under SUMMARY  for DTC description and equivalent MIL code.