Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Idle Air Control Solenoid
Idle Air Control (IAC) solenoid is by-pass air type. Ensure ignition switch is off. Disconnect IAC solenoid harness connector. Measure resistance between IAC solenoid connector terminals. Solenoid has a diode and resistance will be infinite if voltmeter is hooked up wrong. Connect DVOM positive lead to IAC solenoid connector VPWR terminal (Red wire on B-series, White/Red wire on Tribute) and negative lead to IAC terminal (Light Blue wire). Resistance should be 6-13 ohms. If reading is not as specified, replace IAC solenoid. If resistance is 6-13 ohms, IAC solenoid is okay. See appropriate SELF-DIAGNOSTICS article for additional testing and specifications.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.