Error code
OBD2 P2603
OBD2P2603
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
Coolant Pump Control Circuit High.
Severity
moderateCan drive but may cause overheating if not addressed.
Summary
P2603 indicates an issue with the coolant pump motor circuit being too high, specifically related to wiring or the relay in the engine.
Common Causes
- Wiring short to positive
- Engine coolant pump relay
Fixes
FAQ
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More OBD2 codes
- P2600Coolant Pump Control Circuit/Open
- P2601Coolant Pump Control Circuit Range/Performance
- P2602Coolant Pump Control Circuit Low
- P2604Intake Air Heater 'A' Circuit Range/Performance
- P2605Intake Air Heater 'A' Circuit/Open
- P2606Intake Air Heater 'B' Circuit Range/Performance
- P2607Intake Air Heater 'B' Circuit Low
- P2608Intake Air Heater 'B' Circuit High
- P2609Intake Air Heater System Performance
- P2610ECM/PCM Internal Engine Off Timer Performance
- P2611A/C Refrigerant Distribution Valve Control Circuit/Open
- P2612A/C Refrigerant Distribution Valve Control Circuit Low