P2C78

Active Grille Air Shutter Module D Over Temperature

Moderate severity

The control module of active grille air shutter D reports junction temperature above its protection threshold. Thermal protection has triggered.

Common causes

Under-bonnet temperature too high
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $170-880
Sustained stall current
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $170-880
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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

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Frequently asked questions

What does P2C78 mean?

P2C78 means "Active Grille Air Shutter Module D 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 P2C78?

under-bonnet temperature too high; sustained stall current — 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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