Powertrain
Definition only
Lights the check engine lamp
P2D78: Battery Charger Control Module B Processor Performance
Standardized SAE J2012 code · P2Dxx codes
What does P2D78 mean?
The battery charger control module B reports a processor performance fault. CPU watchdog or RAM check failed.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Common causes
- High CPU watchdog repeatedly resets
- Medium RAM check failed
- Low Module software outdated, reflash may resolve
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2D78 on the same make and model first.
P2D78 in the community
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