OBD-II code · Powertrain (generic)

P0CAA Hybrid/EV Battery Temperature Sensor M Circuit Low

The HV battery temperature sensor M reports a circuit low fault. Cell-group temperature monitoring impaired on this channel.

Is it safe to drive with P0CAA?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelySignal wire shorted to ground
  • PossibleInternal sensor short
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • EV/hybrid system warning light on
  • Reduced power output or limp mode
  • Charging may fail or be slowed
  • Reduced electric range

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
0.5–3 h
Emissions test
Usually unaffected
Parts involved
Hv Battery Temp Sensor M, Wiring Harness, Bms

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.