OBD-II code · Powertrain (generic, extended)
P255F A/C Request A Circuit Range/Performance
The A/C request input A is electrically intact, but its value does not match the system context — for example asserted while the HVAC controller reports off, toggling rapidly, or sustained while compressor pressures cannot support it. The ECM disables A/C clutch engagement until the input becomes plausible.
Is it safe to drive with P255F?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyHVAC module sending inconsistent request
- Less likelySensor element aged beyond calibration window
- Less likelySensor mounting loose - signal damping
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.4–2 h
- Emissions test
- Usually unaffected
- Parts involved
- AC Request Input A, HVAC Module
Related codes
- P2519A/C Request A Circuit
- P256FA/C Request B Circuit Range/Performance
- P255CPTO Speed Selector Sensor/Switch 2 Circuit Low
- P255DPTO Speed Selector Sensor/Switch 2 Circuit High
- P255EPTO Speed Selector Sensor/Switch 2 Circuit Intermittent/Erratic
- P2560Engine Coolant Level Low
- P2561A/C Control Module Requested MIL Illumination
- P2562Turbocharger Boost Control Position Sensor A Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.