Connect the IAC valve 3P connector terminal No. 3 and body ground with a jumper wire. IAC VALVE 3P CONNECTOR Wire side of female terminals Check for continuity between ECM/PCM connector terminal A12 and body ground. ECM/PCM CONNECTOR A (31P) Wire side of female terminals Is there continuity? YES - Go to step 13. NO - Repair open in the wire between the IAC valve and the ECM/PCM (A12). Reconnect the jumper wire from the IAC valve 3P connector, then reconnect the IAC valve 3P connector. Turn the ignition switch ON (II).

Measure voltage between body ground and ECM/PCM connector terminal A12. ECM/PCM CONNECTOR A (31P) Wire side of female terminals Is there battery voltage? YES - Substitute a known-good ECM/PCM and recheck. If symptom/indication goes away, replace the original ECM/PCM. NO - Replace the IAC valve.