Powertrain, generic (extended)

P2DBB Battery Charging System B High Voltage Interlock Circuit Intermittent/Erratic

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P2DBB covers an interlock loop of charging system B that keeps dropping out and recovering, so its state flips between valid and invalid. The trigger is usually mechanical: a terminal with low contact pressure, a plug that is not fully latched, or a wire that only loses contact when the body flexes or the parts heat up. No manufacturer documents P2DBB publicly. A useful parallel is Mercedes bulletin LI54.10-P-067823 for the smart electric drive with the 22 kW charger option: loose low-voltage contacts at the charger produced sporadic interlock faults, filed there under the general codes P0A0A and P0A0E, and the car would not charge. CARB expects plug-in hybrids to catch faults that block charging. Steady faults are P2DB7 to P2DBA. Charging may stop for no visible reason.

Likely causes

Loose or widened terminal in an interlock connector
Connector in the charging path not fully latched
Chafed interlock wire that loses contact only with movement or heat

Symptoms

  • Charging via path B stops without warning
  • Fault comes and goes, often depending on temperature

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–900
Time0.5–5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

bcs b hv interlockwiring harnesson board charger

Related codes

P2DB7P2DB8P2DB9P2DBAP0D19

References: static.nhtsa.gov, law.cornell.edu.