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

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.

High severity. Can I keep driving?If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

Symptoms

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

Most 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

What to check, in order

Start with the simplest. You can tick off each step.

Read the codes with a hybrid-compatible scanner and write down the freeze frame data
Compare the reading with other engine data while varying the engine speed.
Make sure the battery cooling air intake is clean
Check the 12 V auxiliary battery, which can also trigger warnings
Leave any high-voltage measurements to a specialized repair shop

Good to know

It can trigger limp mode.
It affects emissions.

What each character of P0C7D means

P: Powertrain: engine and transmission
0: Generic code: same on every make
C: Subsystem depends on the code range
7D: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0C7D?

If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

What causes code P0C7D?

The most common causes are: 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).

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.