Code No. P1239: Trustful Check Engine Speed


FUNCTION



  • Compares the actual engine speed calculated from the crank angle sensor signal cycle with the estimated engine speed calculated from the number of the crank angle sensor signal pulses after a lapse of the specified time.

TROUBLE JUDGMENT


Check Condition
  • Engine is running.
Judgement Criterion
  • The difference between the actual engine speed and the estimated engine speed is more than 500 r/min.
FAIL-SAFE AND BACKUP FUNCTION
  • Throttle opening degree position is in default position.

PROBABLE CAUSE



  • Failed engine-ECU

DIAGNOSIS PROCEDURE

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

  • Reconfirmation of diagnosis code.

Q. Is diagnosis code set?
Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).