P2C66
Hybrid/EV Electronics Coolant Pump A Underspeed
The hybrid electronics coolant pump A runs below the calibrated minimum speed for the commanded duty. Mechanical resistance high or supply voltage low.
The hybrid electronics coolant pump A runs below the calibrated minimum speed for the commanded duty. Mechanical resistance high or supply voltage low.
Common causes
- high
Mechanical load increased
One of the most commonly reported causes for this code — check this first.
Typical part cost: $330-1980
- medium
Supply voltage low under load
A plausible cause — test and verify before replacing parts.
Typical part cost: $330-1980
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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
See related trouble codes
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Frequently asked questions
What does P2C66 mean?
P2C66 means "Hybrid/EV Electronics Coolant Pump A Underspeed". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2C66?
mechanical load increased; supply voltage low under load — 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?
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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