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
Ignition switch is "ON" position
Judgement Criterion
The difference between the actual engine speed and the estimated engine speed is 300 r/min or more.
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 stored?
Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).