Powertrain, generic · Hybrid propulsion

P0BC3 Hybrid/EV Battery Temperature Sensor E Circuit Range/Performance

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

P0BC3 is the plausibility check for battery temperature sensor E, GM's sensor 5: its reading is compared with the other pack sensors, which should agree closely. GM's 2016 hybrid table fails it when E is more than 25 °C away from the average of the others in 50 of 67 samples; the 2018 CT6 plug-in table more than 20 °C for 5 s within 6.7 s; the eAssist mild hybrid (13OBDG05C) allows only 8.55 °C, and only after the module has been off for more than six hours. All are Type B, two trips. The check is suspended while circuit codes are active, so it points to a sensor that reads wrongly but in range, or to a real hot spot. Volt bulletin 18-NA-342 counts it among codes that set falsely in cold weather and fixes them by reprogramming.

Likely causes

Sensor E drifting or poorly seated on its cell group

Module software setting the code falsely in the cold (GM Volt)

Real local hot spot from a weak cell group or blocked airflow

Symptoms

MIL on after two trips
Battery too cold or reduced power message
Limited charge and discharge power

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€60–2,500

Time0.5–5 h

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

Parts involved

hv battery temp sensor ewiring harnessbms

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov.