OBD-II code · Powertrain (generic, extended)
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.
Is it safe to drive with P2D78?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyCPU watchdog repeatedly resets
- PossibleRAM check failed
- Less likelyModule software outdated, reflash may resolve
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–8 h
- Emissions test
- Usually unaffected
- Parts involved
- Battery Charger Cm B
Related codes
- P0E5EBattery Charger Control Module A Processor Performance
- P2D75Battery Charging System Negative Contactor D Control Circuit Low
- P2D76Battery Charging System Negative Contactor D Control Circuit High
- P2D77Battery Charger Control Module B Performance
- P2D79Charging Stop Switch Circuit
- P2D7ACharging Stop Switch Circuit High
- P2D7BCharging Stop Switch Circuit Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.