Powertrain, generic · Hybrid propulsion

P0C7D Hybrid/EV Battery Temperature Sensor G Circuit Range/Performance

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modePossible

P0C7D flags sensor G when its value is electrically valid but does not fit the rest of the pack. GM's 2012 Volt table (12OBDG01A) compares it with the average of the other sensors once propulsion has been off for more than 21,600 s and fails it beyond 25.3 °C in 50 of 67 samples, Type B with two trips; bulletin 18-NA-342 calls it sensor 7 performance. Mitsubishi's Outlander PHEV of 2018 files it as rationality of sensor [06]: after at least 3,600 s soak, with the pack between −30 and 60 °C, a 13 °C gap from the 50-sensor average held for 0.32 s sets it, checked once per drive. Shorts and opens have their own codes P0C7E and P0C7F. Usual causes are a drifting or detached thermistor; GM also fixed false sets on the Volt with new module software.

Likely causes

Thermistor G drifted while staying inside its electrical range

Sensor G no longer seated against its cell group

Battery module software setting the code falsely (GM Volt, 18-NA-342)

Real temperature difference from a weak cell or blocked cooling channel

Symptoms

Check-engine or hybrid warning lamp after a long parking period
Reduced battery power, sometimes a battery-too-cold message

Repair estimate

DifficultyShop_onlyWorkshop job

Parts and labour€80–2,500

Time0.5–5 h

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

Parts involved

hv battery temp sensor gwiring harnessbms

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