Powertrain, generic · Hybrid propulsion

P0CE8 Hybrid/EV Battery Pack Coolant Control Valve Position Sensor Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P0CE8 stands for a valve position feedback that drops out or jumps briefly while the hard low and high limits are not violated long enough to set P0CE6 or P0CE7. Such patterns come from loose pins at the valve plug, a cracked solder joint or a worn sensor track that loses contact at certain angles. GM's 2011 Volt catches a related symptom inside P0CE0: when the summed noise of the feedback exceeds 12 %, the valve performance test fails (8 of 10 samples at 1 s). No manufacturer publicly documents P0CE8 itself; CARB's requirement to monitor battery thermal management inputs applies. Effects range from a brief warning to temporarily limited charging, often with no lasting complaint. Watching the feedback in live data while moving the connector usually reveals the fault.

Likely causes

Loose or corroded pin in the valve connector
Worn sensor track losing contact at certain positions
Cracked solder joint inside the actuator

Symptoms

  • Occasional warning lamp that may go out again
  • Jumping valve position in live data

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–600
Time0.5–3 h

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

Parts involved

hv battery pack coolant valve position sensorwiring harnessbms

Related codes

P0CE6P0CE7P0CE4P0CE5

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