P2C37
Cold Start Engine Coolant Pump Performance
During cold start, the engine coolant pump does not produce the expected flow. Pump aging combined with high cold viscosity, or pump-disable strategy malfunction.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Pump output degraded with ageCommon
- Cold coolant viscosity too highPossible
Parts involved
- Engine Coolant Pump
- Engine Coolant Loop
P2C37 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.