Cooling Fan 1 Control Circuit
Cooling fan control circuit is malfunctioning.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The engine's cooling fan isn't getting the right signals from the computer to turn on or off, which can cause overheating.
What the computer is actually seeing
The Engine Control Module (ECM) expects to see a signal voltage around 0-5 volts from the cooling fan relay circuit. If the voltage is out of this range or nonexistent, it sets this code.
What a healthy reading looks like
The control circuit should show a voltage between 0 and 5 volts when the fan is commanded on. When off, the voltage should be close to 0 volts.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the fuse for the cooling fan circuit. If blown, replace it and clear the code.
- 22. Inspect the wiring and connectors to the cooling fan and relay for damage, corrosion, or loose connections. Repair as needed.
- 33. Use a multimeter to measure the voltage at the fan relay connector with the ignition on and the A/C running. Expect 12 volts at the relay's control pin when the fan should be on.
- 44. If the relay has power, check the fan motor by applying direct power to it. If it doesn't run, replace the fan motor.
- 55. If the fan works, replace the cooling fan relay and retest. If the problem persists, the ECM may be at fault.
Common causes
- Faulty cooling fan relay
- Failed cooling fan motor
- Wiring issues (shorts or opens) in the fan circuit
- Corroded connections
- Faulty Engine Control Module (ECM)
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
You can drive but watch for overheating; fix it soon.
Will this code come back after clearing it?
It might if the underlying issue isn't fixed.
Why does this code sometimes pair with others?
Wiring issues can affect multiple circuits, triggering more than one code.
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