Cause
Faulty engine coolant flow control valve
The motorised valve that routes engine coolant on the module's command — the wax thermostat's electronic replacement. It fails as a motor, as a valve, or as the sensor between them: a winding or driver fault stops it moving, scale and debris bind the rotary element until the motor current gives it away, and a failed position sensor leaves the module driving a valve it cannot verify.
The direction of failure sets the urgency. Stuck toward open is a cold-running engine — inefficient, hard on emissions, safe. Stuck toward closed blocks coolant from the radiator and is an overheat in waiting; the temperature gauge outranks the code list the moment it climbs.
Typically specialist work. Needs equipment or training most home workshops do not have.
Some of these codes mean you should stop driving
1 of the 10 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (10)
Codes where this is a likely explanation first, rather than merely a possible one.
- P2B58 Engine Coolant Flow Control Valve Motor Current High Likely for this code Moderate
- P2B59 Engine Coolant Flow Control Valve Control Circuit/Open Likely for this code Moderate
- P2B5A Engine Coolant Flow Control Valve Control Circuit Low Likely for this code Moderate
- P2B5B Engine Coolant Flow Control Valve Control Circuit High Likely for this code Moderate
- P2B5C Engine Coolant Flow Control Valve Supply Circuit Low Likely for this code Moderate
- P2B5D Engine Coolant Flow Control Valve Position Sensor Circuit Likely for this code Moderate
- P2B5E Engine Coolant Flow Control Valve Position Sensor Circuit Low Likely for this code Moderate
- P2B5F Engine Coolant Flow Control Valve Position Sensor Circuit High Likely for this code Moderate
- P2B60 Engine Coolant Flow Control Valve Position Sensor Circuit Range/Performance Likely for this code Moderate
- P2B61 Engine Coolant Flow Control Valve Stuck Closed Likely for this code Stop driving High
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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