P2561A/C Control Module Requested MIL Illumination
- 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
- P2561 is a messenger code. The climate control module has found an emission-relevant fault in its own area, such as a component that feeds the engine's A/C idle strategy, and asks the engine module to switch on the warning lamp, since only the master controller may drive it. The engine module stores P2561 as a pointer; the actual fault code sits in the A/C module and must be read there. GM's 2012 hybrid table 12OBDG06 illustrates this split: the ECM is the master that controls the lamp, while other controllers store their own codes. CARB's section (e)(12) explains why A/C faults can be emission-relevant at all: wherever the A/C changes fuel or spark control, its electronic parts must be monitored. No maker documents P2561 publicly. Clearing it without fixing the A/C fault brings it back.
- What you may notice
- Check engine light on
- A/C may not cool or may be switched off
- Further codes stored in the climate control module
- Likely causes
- LikelyEmission-relevant fault stored in the climate control module
- PossibleFailed A/C sensor or actuator behind that fault
- RareClimate control module internal or software fault
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.