Powertrain, generic (extended)

P2C95 Hybrid/EV Battery Contactor Control Supply Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2C95 is the upper-limit counterpart of P2C94: the voltage on the feed for the contactor coil drivers exceeds what the battery controller accepts. An excessive supply is less common than a weak one, but it heats the coils and stresses the driver transistors, and it can mean the measurement is wrong, for instance when the sense line touches a higher potential or the feed regulator inside the controller has failed. LG Energy Solution patent US12007445B2 shows that controllers measure this supply before each contactor closes; an upper limit is the logical extension, although the patent itself deals with undervoltage. No manufacturer documents P2C95 publicly. Depending on strategy the controller may refuse to close contactors or open them, so loss of ready mode is possible. CARB requires monitoring of hybrid components.

Likely causes

Supply or sense line shorted to a higher voltage
Supply regulator or measurement in the battery controller faulty
12 V system overvoltage from a faulty DC/DC converter or jump start

Symptoms

  • Hybrid or EV system warning
  • Vehicle may not become ready or may shut down HV

Repair estimate

DifficultyHardWorkshop job
Parts and labour€50–3,000
Time0.5–6 h

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

Parts involved

hybrid battery contactor control supplywiring harnessbms

Related codes

P2C92P2C93P2C94P0ADC

References: law.cornell.edu, patents.google.com.