P2DA4
Coolant Heater A Internal Control Module Performance
The internal control module of coolant heater A reports a performance fault. Internal self-tests fail.
The internal control module of coolant heater A reports a performance fault. Internal self-tests fail.
Common causes
- high
Internal module fault
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-1320
- medium
Firmware corruption
A plausible cause — test and verify before replacing parts.
Typical part cost: $220-1320
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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 P2DA4 mean?
P2DA4 means "Coolant Heater A Internal Control Module Performance". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2DA4?
internal module fault; firmware corruption; module software outdated, reflash may resolve — these are the most commonly reported causes.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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