P0EA9
- Powertrain
- Generic (SAE)
Get it looked at now
Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
Auxiliary Cooling System Performance
This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.
The auxiliary cooling system performance is below calibration. Coolant flow or temperature drop insufficient under load.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
- Urgency
- Get it looked at now
- Will it pass emissions
- Not affected
- Check engine light
- Solid
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Aux pump output degraded | Very common | — |
| 2 | Radiator partially blocked | Common | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
- Aux Cooling Pump
- Aux Cooling Radiator
- Aux Cooling Fan
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Awaiting review
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