Powertrain, generic · Hybrid propulsion

P0CF9 Control Pilot Charging Switch A Range/Performance

Check engine lightOn
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

Charging switch A is the vehicle-side switch that adds a resistor across the pilot to tell the charging station that the car is ready to take current. P0CF9 says the effect of that switch is implausible. GM documents the check for the Chevrolet Volt 2011-2019 (VICM/HPC2): with the cord unplugged, the controller closes its diagnostic switch together with the charging switch and expects the ratio of pilot voltage to battery voltage between 0.14 and 0.28; outside that band in 30 of 50 samples at 100 ms the code sets, Type A, MIL after one trip. The test only runs once the pilot circuit check has passed in the same key cycle, and it comes before the ventilation switch test P0D01. Opens and shorts of the switch are P0CF8, P0CFA and P0CFB. A car with this fault may be recognised but not charge.

Likely causes

Charging switch resistor branch out of tolerance or switch with high contact resistance
Internal fault in the VICM/charging module measuring or switching circuit
Leakage on the pilot line from moisture in the charge inlet

Symptoms

  • Malfunction indicator lamp on (GM Type A)
  • Charging does not start or is refused

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–1,200
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

P0CF4P0CF8P0CFAP0CFBP0CFDP0D01

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com, en.wikipedia.org.