P26FD
A/C Compressor Internal Control Module Performance
The internal control module of an electrically driven A/C compressor (typical on hybrid and BEV vehicles) reports an internal performance fault. Compressor capacity may be reduced or shut down.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
Symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Common causes
Ordered by how often each turns out to be the cause.
- Internal fault in compressor inverter electronicsCommon
- Software error in compressor control logicPossible
- Module software outdated, reflash may resolveLess likely
Parts involved
- Electric AC Compressor
- Compressor Inverter
P26FD is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.