Powertrain, generic · Hybrid propulsion

P0C80 Hybrid/EV Battery Temperature Sensor G Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0C80 catches a sensor G signal that jumps around instead of following the slow thermal drift of a large battery. GM spells out the logic in its hybrid tables 18OBDG02 and 19OBDG02: every 100 ms the module sums the absolute changes of the reading across a 10-sample window, a total above 10 fails that window, and 4 failed windows out of 5 set the code as Type B, two trips, provided system voltage exceeds 10.2 V and the battery interface module is communicating. Mitsubishi's Outlander PHEV has no erratic code for this sensor. The value stays inside its valid range, which separates P0C80 from P0C7E and P0C7F; a loose terminal or a cracked conductor is the usual reason. When several sensors on one board jump together, suspect the board or its supply.

Likely causes

Loose or fretting terminal in the sensor G connector
Conductor cracked inside the insulation, breaking under vibration
Cell monitoring board with unstable reference or ground

Symptoms

  • Warning lamp that may come and go between trips
  • Jumping sensor G value in live data
  • Occasional power reduction

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–2,500
Time1–5 h

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

Parts involved

hv battery temp sensor gwiring harnessbms

Related codes

P0C7CP0C7DP0C7EP0C7FP0C37P0C85

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