P2DE9
Cold Start Engine Coolant Pump Underspeed
During cold start, the engine coolant pump runs below the calibrated minimum speed. Cold viscosity load too high or pump weak.
During cold start, the engine coolant pump runs below the calibrated minimum speed. Cold viscosity load too high or pump weak.
Common causes
- high
Cold coolant viscosity too high
One of the most commonly reported causes for this code — check this first.
Typical part cost: $330-1980
- medium
Pump output degraded
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 P2DE9 mean?
P2DE9 means "Cold Start Engine Coolant Pump 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 P2DE9?
cold coolant viscosity too high; pump output degraded — 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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