All codes/P2DA6

P2DA6

Coolant Heater A Over Temperature

Moderate severity

Coolant heater A reports temperature above the protection threshold. Coolant flow blocked or thermistor failed.

Coolant heater A reports temperature above the protection threshold. Coolant flow blocked or thermistor failed.

Common causes

  • Coolant flow through heater blocked

    One of the most commonly reported causes for this code — check this first.

    high

    Typical part cost: $220-1320

  • Thermistor failed

    A plausible cause — test and verify before replacing parts.

    medium

    Typical part cost: $220-1320

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First things to check

  1. 1Confirm the code with a scan tool and check for additional related codes.
  2. 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P2DA6 mean?

P2DA6 means "Coolant Heater A Over Temperature". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P2DA6?

coolant flow through heater blocked; thermistor failed — 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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