High Idle Speed
- Check switch condition signal circuit. See CODE 51 in appropriate article;
For GS300 TESTS W/CODES
For SC300 TESTS W/CODES
For SC400 TESTS W/CODES
- Check Idle Air Control (IAC) valve circuit.
- Check A/C signal circuit.
- Check ECM power source circuit (ignition keyed).
- Check Park/Neutral Position (PNP) switch circuit (clutch start switch circuit on SC300 M/T).
- Check ECM back-up power circuit (battery).