P2B5B

Engine Coolant Flow Control Valve Control Circuit High

Moderate severity

The engine coolant flow control valve reports a control circuit high condition. Coolant routing between engine and radiator branches cannot be commanded as expected.

Common causes

Control wire shorted to B+
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $170-770
Open valve motor
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $170-770
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P2B5B mean?

P2B5B means "Engine Coolant Flow Control Valve Control Circuit High". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P2B5B?

control wire shorted to b+; open valve motor; connector pins corroded - high contact resistance — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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