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 JUDGEMENT
Check Condition
The engine speed monitored with a 120 degree- cycle pulse is more than 500 r/min.
Judgement Criterion
The difference between the engine speed monitored with a 120 degree-cycle pulse and the engine speed monitored with a 10 degree-cycle pulse is more than 500 r/min.
Check Condition
The engine speed monitored with a 120 degree- cycle pulse is less than 500 r/min.
Judgement Criterion
The engine speed monitored with a 10 degree- cycle pulse is more than 1,000 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 ).