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Diagnostic Procedure

NO. 2 CHECK ENGINE LIGHT ILLUMINATES DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 VERIFY PCM DTC 
Yes Go to the applicable DTC inspection. (See DTC TABLE .)
No Go to the next step.
2 INSPECT COMMUNICATION LINE BETWEEN PCM AND INSTRUMENT CLUSTER 
  • Inspect for a short or open circuit between the following terminals:
    • Instrument cluster terminal 1B-BCM terminal 2D
    • Instrument cluster terminal 1D-BCM terminal 2C
    • BCM terminal 3C-PCM terminal 2AK
    • BCM terminal 3D-PCM terminal 2AL
  • Is the wiring harness normal?
Yes Inspect the instrument cluster. (See INSTRUMENT CLUSTER INSPECTION .)
No Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Instrument cluster terminal 1B-BCM terminal 2D
  • Instrument cluster terminal 1D-BCM terminal 2C
  • BCM terminal 3C-PCM terminal 2AK
  • BCM terminal 3D-PCM terminal 2AL
If there is a common connector: 
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground or open circuit.
  • Repair or replace the malfunctioning part.
If there is no common connector: 
  • Repair or replace the wiring harness which has a short to ground or open circuit.
3 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX .)
  • If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
    • If the vehicle is repaired, troubleshooting is completed.
    • If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.


NO. 2 CHECK ENGINE LIGHT ILLUMINATES DIAGNOSTIC PROCEDURE

STEP INSPECTION RESULTS ACTION
1 VERIFY PCM DTC 
Yes Go to the applicable DTC inspection. (See DTC TABLE .)
No Go to the next step.
2 INSPECT COMMUNICATION LINE BETWEEN PCM AND INSTRUMENT CLUSTER 
  • Inspect for a short or open circuit between the following terminals:
    • Instrument cluster terminal 1B-BCM terminal 2D
    • Instrument cluster terminal 1D-BCM terminal 2C
    • BCM terminal 3C-PCM terminal 2S
    • BCM terminal 3D-PCM terminal 2T
  • Is the wiring harness normal?
Yes Inspect the instrument cluster. (See INSTRUMENT CLUSTER INSPECTION .)
No Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Instrument cluster terminal 1B-BCM terminal 2D
  • Instrument cluster terminal 1D-BCM terminal 2C
  • BCM terminal 3C-PCM terminal 2S
  • BCM terminal 3D-PCM terminal 2T
If there is a common connector: 
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground or open circuit.
  • Repair or replace the malfunctioning part.
If there is no common connector: 
  • Repair or replace the wiring harness which has a short to ground or open circuit.
3 Verify the test results.
  • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX .)
  • If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
    • If the vehicle is repaired, troubleshooting is completed.
    • If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.