P0ECA
A/C Refrigerant Temperature Sensor B Circuit Low
The ECM detects a low fault on the a/c refrigerant temperature sensor b circuit. Reading cannot be used reliably for control.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Signal wire shorted to groundCommon
- Internal sensor shortPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- AC Refrigerant Temp Sensor B
- Wiring Harness
P0ECA 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.