P0CF2: Hybrid/EV Electronics Coolant Temperature Sensor A Circuit Intermittent/Erratic

This code catches a coolant temperature signal that jumps around faster than a liquid can actually change temperature, without necessarily leaving the valid voltage window. GM computes a string length: the controller adds up the absolute steps between four consecutive readings taken 250 ms apart. If that total exceeds 90 °C (2016 Volt, 19OBDG01) or 95 °C (16OBDG02), the window counts as failed; 4 of 5 windows, 5 of 7 windows or 1 s in a 1.25 s window then set the code, Type B, two trips. Loose terminals, a cracked solder joint in the sensor or a chafed wire that touches intermittently produce such spikes. Steady faults are P0CF0/P0CF1, a stable but wrong value P0CEF. The erratic reading can make the pump and power limits react without reason.

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

Malfunction indicator lamp, sometimes coming and going
Coolant temperature value jumps in live data
Pump speed or power limits change without reason

Most likely causes

Loose or spread terminal in the sensor connector
Chafed wire making intermittent contact with ground or another circuit
Cracked internal connection in the sensor

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
Gently move the wiring with the engine running and watch whether the reading changes.
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

Repair difficulty: medium
It can trigger limp mode.
It affects emissions.

What each character of P0CF2 means

P: Powertrain: engine and transmission
0: Generic code: same on every make
C: Subsystem depends on the code range
F2: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0CF2?

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 P0CF2?

The most common causes are: loose or spread terminal in the sensor connector; chafed wire making intermittent contact with ground or another circuit; cracked internal connection in the sensor.

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.