OBD-II code family
Cooling Fan Control and Speed Faults (15 codes)
15 related fault descriptions. Use each full code and the exact vehicle service information to identify its circuit, monitored condition, and required tests.
Codes in this family
This is the complete published member list for this guide. Each code retains its own page; shared diagnostic context does not mean that every member has the same test or repair.
- P0480Cooling Fan 1 Control Circuit
- P0481Cooling Fan 2 Control Circuit
- P0482Cooling Fan 3 Control Circuit
- P0483Cooling Fan Rationality Check Failed
- P0484Cooling Fan Circuit Over Current
- P0485Cooling Fan Power/Ground Circuit Malfunction
- P0493Fan Overspeed
- P0494Fan Speed Low
- P0495Fan Speed High
- P0691Cooling Fan 1 Control Circuit Low
- P0692Cooling Fan 1 Control Circuit High
- P0693Fan 2 Control Circuit Low
- P0694Fan 2 Control Circuit High
- P0695Fan 3 Control Circuit Low
- P0696Fan 3 Control Circuit High
What these codes mean
P0480, P0481 and P0482 identify numbered fan-control circuits. P0691/P0692 add low/high control results for circuit 1, P0693/P0694 for circuit 2 and P0695/P0696 for circuit 3. P0483 concerns rationality, P0484 overcurrent and P0485 power/ground. P0493 names overspeed, while P0494/P0495 distinguish low/high fan speed. A control-circuit high result and a high-speed result are different conditions; keep each exact code when choosing a test.
Circuit 1, 2 or 3 does not establish the number of motors, relays or speed stages. Identify the installed electric-fan, fan-clutch and controller arrangement, full code and required command state. Fan noise, visible movement and a scan-tool speed are different observations; the feedback itself can need validation.
Audi’s September 2024 bulletin 19-24-67 uses supply and PWM checks for its listed 2021–2024 applications with P048000/P048100. Ford SSM 47999 covers specified 2016–2019 6.7L F-Super Duty/F650–750 vehicles with a fan that stays on or is inoperative, including P0480/P0494/P0495. It directs an updated diagnostic path to avoid unnecessary clutch replacement. Neither example makes these codes exclusively electric or mechanical.
The low/high control examples also depend on the installed monitor. Mitsubishi’s cited 2022 PHEV-ECU information compares commanded and observed radiator/condenser relay states for P0691–P0694. Ford’s covered 2023–2024 diesel summary allows an open or a short to ground for P0693 and a short to power for P0694. Use the required command state and actual circuit diagram; a generic high/open or low/ground translation is not sufficient.
On the cited 2009 Durango 2WD 5.7L Hybrid, the HGM monitors the N27 fan-3 control circuit: P0695 detects short to ground and P0696 short to voltage under their specified conditions. The low-code procedure also considers open wiring and a stalled/obstructed fan. These are bounded application examples, not evidence of three relays, a universal third high-speed stage or a socket that must be replaced. The hybrid procedure requires its high-voltage precautions before work near high-voltage components.
Save the scan, actual temperature warnings and operating history. Inspect only accessible cooled connections after the required isolation. A key removed from the vehicle does not by itself establish safe fan access. Do not stop, spin or load a fan by hand, bridge a relay, feed an unidentified controller directly or reproduce an overheating condition on the road.
Have the specified supply, return, control, speed-feedback and component checks performed. An overcurrent result does not alone prove a binding motor or successful protective shutdown; low/high speed does not establish which part failed. Repair the demonstrated condition and verify the relevant control and monitor. Follow the vehicle’s overheating instructions and obtain an itemized quote for the confirmed job.
Identify the circuit on your vehicle
Match the full DTC, reporting module, and any failure-type suffix to the service information for your exact year, make, model, engine, and equipment. An identifier alone does not establish installed hardware count, location, connector pinout, or a universal measurement.
Where the manufacturer publishes its own meaning for this code, that is the one to work from — it describes the actual component on your vehicle, which the generic definition cannot. Keep the generic description for what it is good for: it tells you which subject area the standard assigned the code to, which is useful context when the two appear to disagree. If they do disagree, follow the manufacturer.