Powertrain, generic · Hybrid propulsion

P0B2B Hybrid/EV Battery C Voltage

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modePossible

P0B2B is the general voltage fault of hybrid/EV battery C, the third sub-battery or energy store that a controller can monitor on its own. It signals an implausible voltage of this unit without the detail given by P0B2C (unstable), P0B2D (low) or P0B2E (high). Which modules form battery C, and whether a vehicle has a third unit at all, depends on the manufacturer; no manufacturer documents P0B2B publicly. As a reference GM monitors the voltage of the whole pack with P0ABB to P0ABD, among them a plausibility check against the cell sum. CARB requires voltage sensors and cells of hybrid storage to be monitored and faults to point to the replaceable unit. Expect a hybrid warning and limited battery power.

Likely causes

Weak or failing cells or module in battery C

Fault in the voltage sense leads or connectors of battery C

Battery controller software or internal measurement fault

Symptoms

Hybrid/EV system or high-voltage battery warning on
MIL on
Battery power limited, less electric drive or assist
Charging or recuperation restricted

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€100–4,000

Time1–10 h

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

Parts involved

hv battery cbms

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