Code No. P1971: Fail-safe Control Monitoring


FUNCTION



TROUBLE JUDGMENT


Check Condition
Judgment Criterion

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q. Is any other diagnosis code than P1971 output?
Inspection chart for diagnosis code (Refer to ).
Go to Step 2 .

STEP 2. M.U.T.-III diagnosis code

  • After clearing the diagnosis code through M.U.T.-III, start the engine and confirm whether the diagnosis code is output.

Q. Diagnosis code set?
Replace the engine-ECU or engine-A-M/T-ECU then perform the variant coding (Refer to GROUP 00 - Precautions Before Service - How to Perform Variant Coding ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).