Powertrain, generic · Hybrid propulsion

P0DE9 Hybrid/EV Battery Pack Coolant Control Valve C Performance/Stuck Off

Check engine lightOn

EmissionsRelevant

Drive cycleRequired

Limp modeNo

P0DE9 says coolant control valve C is electrically fine but does not do its job: it fails to reach the commanded position or remains in its off state. No manufacturer documents P0DE9 publicly. GM's 2011 Chevrolet Volt tables show what such a test can look like for valve A, which has a position feedback: on start-up the valve must find its end stop within 800 ms, later it must reach each target within 1.5 s, and an erratic feedback with more than 12 % noise counts as well; enough failed samples set a Type B code with the MIL on the second trip. Where no feedback exists, makers judge the valve from coolant or pack temperatures, which CARB requests as a functional check of cooling. Dirt, a seized valve body or a weak actuator are typical. Stuck on is P0DEA.

Likely causes

Valve body seized or sluggish from deposits

Worn actuator motor or gearing in valve C

Low coolant or air in the battery loop distorting the temperature check

Overly tight diagnostic calibration

Symptoms

Battery heats up faster under load or while fast charging
Charging power or drive power limited
Malfunction indicator lamp on

Repair estimate

DifficultyMediumWorkshop job

Parts and labour€100–900

Time1–4 h

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

Parts involved

hv battery pack coolant valve cwiring harnessbms

Related codes

P0DEA P0DE8 P0CE0 P0D1B P0CE5

References: gsi.ext.gm.com, law.cornell.edu, static.nhtsa.gov.