Powertrain, generic · Hybrid propulsion

P0C71 Hybrid/EV Battery Temperature Sensor D/E Correlation

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0C71 checks whether battery temperature sensors D and E agree with each other. Both sit in the same pack, so after a long soak they should report almost the same value; a lasting gap means one of them reads wrong although its circuit looks healthy. No manufacturer documents P0C71 publicly. GM and Mitsubishi run this plausibility test against the pack average instead and log the single sensor: on the eAssist cars (13OBDG05C) GM flags sensor 4 (P0AE9) or sensor 5 (P0BC3) beyond 8.55 °C after more than 21,600 s off, Type B, while the 2022 Outlander PHEV tolerates 13 °C after one hour. P0C70 covers the C/D pair and P0C72 the E/F pair; open or shorted sensors set their own circuit codes.

Likely causes

Thermistor D or E drifted while staying inside its electrical range
Sensor no longer pressed against its cell or module
Genuine temperature difference from uneven cooling or a weak cell group
Battery management software with an overly tight comparison

Symptoms

  • Hybrid or EV system warning lamp
  • Reduced battery charge and discharge power
  • Battery cooling running more often than usual

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–2,500
Time0.5–6 h

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

Parts involved

hv battery temp sensor dhv battery temp sensor ebms

Related codes

P0C70P0C72P0AE9P0BC3

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