P0CBF: Drive Motor A Coolant Temperature Sensor Circuit High

P0CBF is the code for an excessive signal from the coolant temperature sensor of drive motor A. With an NTC element a very high resistance stands for extreme cold, so in practice an open sensor, a broken wire or a disconnected plug is behind it. In GM's 2013 eAssist table 13OBDG05C the code is set when the raw value exceeds 176,962 Ω, the equivalent of −40 °C, in 50 of 62 samples at 100 ms with ignition in run/crank, Type B, two trips. Because −40 °C is a real if rare ambient temperature, the check uses a resistance far beyond the normal working curve. With the loop temperature unknown, the system has to fall back on substitute values and may scale back the electric assist. The codes P0CBD and P0CC2 rely on this sensor and are blocked while P0CBF is present; P0CBE is its low counterpart.

Symptoms

• Check-engine lamp after two trips
• Coolant temperature of the motor shown at minimum value

Most likely causes

• Open signal or return wire, or unplugged sensor
• Sensor element open internally
• Corroded pins at sensor or control module

What to check, in order

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

1. Read the codes with a hybrid-compatible scanner and write down the freeze frame data
2. Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
3. Make sure the battery cooling air intake is clean
4. Check the 12 V auxiliary battery, which can also trigger warnings
5. 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 P0CBF means

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

Frequently asked questions

Can I keep driving with code P0CBF?

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 P0CBF?

The most common causes are: open signal or return wire, or unplugged sensor; sensor element open internally; corroded pins at sensor or control module.

Related codes

• P0CBEDrive Motor A Coolant Temperature Sensor Circuit Low
• P0CBDDrive Motor A Coolant Temperature Sensor Circuit Range/Performance
• P0CBCDrive Motor A Coolant Temperature Sensor Circuit
• P0CC0Drive Motor A Coolant Temperature Sensor Circuit Intermittent
• P0A2DDrive Motor A Temperature Sensor A Circuit High

Sources

• gsi.ext.gm.com: 13OBDG05C Hybrid Diagnostics
• law.cornell.edu: 13 CCR 1968.2

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.