Test No. 1
- Turn ignition on for more than 15 seconds. DO NOT start engine. Turn ignition off. This should fully retract ISC plunger.
- Ensure ISC plunger is in fully retracted position. Disconnect harness connector(s) from ISC motor. Turn ignition on. DO NOT start engine.
- Backprobe Green/White wire terminal No. 19 and Black (Green/Black on some models) wire terminal No. 24 at Engine Control Unit (ECU) wiring harness connector using digital voltmeter. Note TPS output voltage.
- If output voltage is within .48-.52 volt, go to step 6). If output voltage is not within .48-.52 volt, loosen TPS mounting screw(s) and rotate TPS clockwise or counterclockwise until output voltage is within specification. Tighten TPS mounting screws.
- Turn ignition off. Reconnect harness connector(s) at ISC motor. Start engine. Ensure engine idles within curb idle speed specification.
- Turn ignition off. Disconnect negative battery cable for at least 15 seconds to clear diagnostic trouble code. Reconnect negative battery cable. Operate engine at idle for approximately 5 minutes to ensure engine idles smoothly.