Powertrain, generic · Hybrid propulsion

P0CFB Control Pilot Charging Switch A Circuit High

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

P0CFB is the high-side counterpart: the control or feedback line of charging switch A, which loads the pilot with an extra 1.3 kΩ to request charging, shows a voltage above its valid band. Typical are a short to a supply voltage in the harness or connector, or an output stage in the charging module that no longer pulls the line down. No manufacturer documents this code publicly; the closest documented test is GM's P0CF9 on the Chevrolet Volt, which judges the switch by the pilot voltage it produces in a self-test (ratio 0.14-0.28), while CARB requires plug-in vehicles to monitor the charging system. Low readings are P0CFA, an open line P0CF8, dropouts P0CFC. For the driver the station typically stays in the plugged-in state without supplying power, or a session cannot be ended cleanly.

Likely causes

Switch control or feedback wire shorted to a supply voltage
Output stage in the charging module no longer switching to ground
Lost ground at the switch letting the line float high

Symptoms

  • Vehicle detected at the station but no energy flows
  • Charging cannot be stopped normally

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–900
Time0.5–3 h

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

Parts involved

control pilot switch awiring harnesson board charger

Related codes

P0CF8P0CF9P0CFAP0CFCP0CFD

References: law.cornell.edu, en.wikipedia.org, gsi.ext.gm.com.