Powertrain, generic · Hybrid propulsion

P0CB6 Hybrid/EV Battery Temperature Sensor O Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0CB6 targets a sensor O signal that jitters or jumps instead of changing smoothly. Only GM's later HPC2 tables (16OBDG02 to 19OBDG02) define it: every 100 ms a sample is taken, the absolute steps between ten consecutive samples are summed, and a sum above 10 marks that window as failed. Four failed windows out of five set the code as Type B, so the lamp follows on the second trip; the test needs more than 10.2 V and a working link to the battery interface module. The earlier Volt tables of 2011 and 2012 had no such code for O, and Mitsubishi uses none for its pack sensors. Because the reading can stay inside the valid band, P0CB4 and P0CB5 may never appear. Shaking the harness while watching live data, and the freeze-frame record, help to find a fretting contact or cracked solder joint.

Likely causes

Fretting or loose terminal in the sensor O circuit
Cracked solder joint or trace on the sensing board
Chafed lead touching ground only under vibration

Symptoms

  • Warning lamp that comes and goes
  • Sensor O value jumping in live data

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 owiring harnessbms

Related codes

P0CB2P0CB3P0CB4P0CB5P0CB1P0CBB

References: gsi.ext.gm.com, gsi.ext.gm.com.