Powertrain, generic · Hybrid propulsion

P0CBF Drive Motor A Coolant Temperature Sensor Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

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.

Likely causes

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

Symptoms

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

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€60–450
Time0.5–2 h

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

Parts involved

drive motor a coolant temp sensorwiring harnesshybrid control module

Related codes

P0CBEP0CBDP0CBCP0CC0P0A2D

References: gsi.ext.gm.com, law.cornell.edu.