Diagnostic trouble code
P0691
Powertrain
Unverified
Powertrain (P)
Cooling
Cooling fan relay 1 control circuit low
The cooling fan relay 1 circuit reads too low.
What P0691 means
The cooling fan relay 1 circuit reads too low.
Symptoms you may notice
- Fan runs constantly or never
- Overheating in traffic
Possible causes
- Shorted relay circuit
- Faulty relay
- Wiring short
Causes are listed from most to least likely for this code. Confirm the actual cause with the diagnostic checks before replacing parts.
Checks to run
- Test the relay
- Check wiring
- Verify fan operation
Tools you may need
Multimeter
Related codes
More Cooling codes →
P0115
Engine coolant temperature sensor circuit malfunction
P0117
Engine coolant temperature sensor circuit low input
P0118
Engine coolant temperature sensor circuit high input
P0125
Insufficient coolant temperature for closed-loop fuel control
P0128
Coolant thermostat below regulating temperature
P0217
Engine coolant over temperature condition
Verification and editorial notes
UnverifiedThis page has not been technically verified yet. Confirm the diagnosis and measurements in the workshop manual for your vehicle.
Diagnose before replacing. A diagnostic trouble code identifies the circuit or
system the control unit flagged. It does not prove that a particular part has failed. Confirm
the cause with the measurements and checks above, and follow the workshop manual for your exact
engine before replacing parts or clearing codes.