Test NTC-8: Checking Idle Air Control Motor Operation

NOTE: For circuit identification, see WIRING DIAGRAMS article. After each repair procedure has been completed, reconnect all components. Perform TEST VER-5 to ensure system is functioning properly. Ensure no DTCs are present before performing this test.

Start engine and let idle. Using scan tool, access ACTUATOR TESTS and set Idle Air Control (IAC) motor to 1400 RPM. If engine speed does not increase to 1400 RPM, go to next step. If engine speed increases to 1400 RPM, no problem is indicated at this time. Test is complete.
Turn ignition off. Disconnect IAC motor 4-pin connector. Disconnect PCM connectors. PCM is located on left side of engine compartment, between Power Distribution Center (PDC) and Transmission Control Module (TCM). See Figure. Visually inspect connectors for corroded, damaged, pushed-out or miswired terminals. Repair connectors as necessary. If connectors are okay, between resistance of each IAC driver circuit between IAC motor harness connector and PCM C2 harness connector. See IAC DRIVER CIRCUIT IDENTIFICATION table. See Figure and Figure . If all resistances are less than 5 ohms, replace IAC motor. If any resistance is 5 ohms or more, repair open in appropriate circuit.

IAC DRIVER CIRCUIT IDENTIFICATION

IAC Motor Connector Terminal No.	Wire Color	PCM C2 Connector Terminal No.
1	Gray/Red	57
2	Yellow/Black	49
3	Brown/White	48
4	Violet/Black	58