Powertrain, generic · Hybrid propulsion

P0B1A Hybrid/EV Battery Pack Voltage Sense C Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0B1A flags pack voltage measurement C as in range but not believable. The controller compares it with a reference, usually the sum of the cell voltages or another pack voltage reading, and sets the code when the difference stays too large. No manufacturer documents P0B1A publicly. As an analogue, GM fails P0ABB on channel A once pack voltage and summed cell voltages differ by more than 12 V for 20 of 25 samples, Type A. CARB requires rationality monitoring for battery voltage sensors of hybrid storage systems. Electrical faults of channel C are P0B19, P0B1B and P0B1C. A distorted pack voltage undermines state of charge and cell protection, so power or charging is restricted.

Likely causes

Drift or calibration error of measurement channel C
Cell voltage acquisition faulty, reference sum wrong
Increased resistance at sense terminals
Battery controller software needs an update

Symptoms

  • MIL and hybrid/EV system warning on
  • Implausible state-of-charge or range display
  • Battery power limited, reduced electric drive or assist

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–2,500
Time1–6 h

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

Parts involved

hv battery pack voltage sense cwiring harnessbms

Related codes

P0B19P0B1BP0B1CP0B1DP0B15P0ABB

References: gsi.ext.gm.com, law.cornell.edu.