P0495 Cooling Fan Speed High

P0495 indicates cooling fan speed is higher than expected. The fan may be running faster than commanded or the speed feedback may be reporting too high.

Code details

Generic OBD-II · P0

System: Emissions
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not replace temperature sensors for P0495 until fan command, module control, and speed feedback are verified.

Symptoms of P0495

Check-engine light, often with no obvious change in how the car drives.
A failed emissions test or incomplete readiness monitors.
Sometimes a faint fuel-vapour smell (on EVAP codes).

Common causes of P0495

A worn catalytic converter or an oxygen/air-fuel sensor reading out of range.
EVAP leaks — a loose or failed gas cap, cracked hose, or purge/vent valve.
Exhaust leaks, fuel-trim problems, or a fault in a related monitor.

Useful checks before replacing parts

Review commanded fan speed, actual fan speed feedback, coolant temperature, A/C pressure, module command, relay state, and freeze-frame conditions.
Inspect stuck relay contacts, fan module faults, speed feedback wiring, shorted control circuits, incorrect fan assemblies, and calibration issues.
Compare fan behavior at low, medium, and high commands to identify whether the fan or feedback signal is over-reporting.

Related OBD-II codes

These nearby emissions entries can help compare wording and pin down the fault area.