P2D78
Battery Charger Control Module B Processor Performance
The battery charger control module B reports a processor performance fault. CPU watchdog or RAM check failed.
The battery charger control module B reports a processor performance fault. CPU watchdog or RAM check failed.
Common causes
- high
CPU watchdog repeatedly resets
One of the most commonly reported causes for this code — check this first.
Typical part cost: $550-3300
- medium
RAM check failed
A plausible cause — test and verify before replacing parts.
Typical part cost: $550-3300
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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 P2D78 mean?
P2D78 means "Battery Charger Control Module B Processor 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 P2D78?
cpu watchdog repeatedly resets; ram check failed; module software outdated, reflash may resolve — these are the most commonly reported causes.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?
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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