P0EA9
Auxiliary Cooling System Performance
The auxiliary cooling system performance is below calibration. Coolant flow or temperature drop insufficient under load.
The auxiliary cooling system performance is below calibration. Coolant flow or temperature drop insufficient under load.
Common causes
- high
Aux pump output degraded
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-1650
- medium
Radiator partially blocked
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-1650
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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 P0EA9 mean?
P0EA9 means "Auxiliary Cooling System Performance". It is a generic OBD-II code that points to a fault in the hybrid / ev powertrain.
What are the most common causes of P0EA9?
aux pump output degraded; radiator partially blocked — 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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