P0527Fan Speed Sensor Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- Engine-driven fans with an electronically controlled viscous clutch (GM petrol SUVs and pick-ups 2004–2006, GM Duramax, Ford 6.7 L Power Stroke) have a Hall sensor reporting fan speed; the fan checks P0483, P0494 and P0495 need it. P0527 means a signal is present but implausible – spikes, jumps or a speed that does not fit the clutch command and engine speed. No manufacturer document available to us uses P0527; GM covers implausibility through P0483 (target versus actual) and P0493. CARB requires input components used by other diagnoses to be checked for plausibility.
- What you may notice
- Check engine light (depending on the maker)
- Unsteady fan control
- Fan permanently on
- Likely causes
- PossibleSensor or trigger element damaged, wrong air gap
- PossibleInterference or ground fault on the sensor line
- PossibleViscous clutch slipping or sticking (real speed off)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €80 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.