Powertrain, generic · Hybrid propulsion

P0DB0 Hybrid/EV Battery Cell Balancing Circuit B

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0DB0 flags an electrical defect in the second balancing circuit, B. The battery controller finds an open, short or implausible voltage on the switch, resistor or lead serving that cell group, independent of whether balancing would be needed right now. One way to test this hardware is shown in LG Chem's patent US20110285539A1: a floating capacitor is charged to the cell voltage and then drained via the bleed path, and a high leftover voltage marks the circuit as faulty. CARB 13 CCR 1968.2 requires functional monitoring of these parts on hybrids. Audi lists P0DB000 in bulletin 2046556, written for the 2016 A3 e-tron, next to the other circuit codes; there it came with intermittent charging refusal and was fixed by software for J840 and JX1.

Likely causes

Damaged balancing/sense lead or connector of cell group B
Cell monitoring chip or controller of group B defective
Short 12 V supply dropout during service work

Symptoms

  • Battery system warning and MIL
  • Electric drive or assistance possibly limited

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€200–4,000
Time1–8 h

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

Parts involved

hv battery cell balancing circuit bbms

Related codes

P0DABP0DB1P0DB2P0DB3P0DACP0DB4

References: law.cornell.edu, patents.google.com, static.nhtsa.gov.