Powertrain, generic · Hybrid propulsion

P0AE8 Hybrid/EV Battery Temperature Sensor D Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

Battery temperature sensor D is a further thermistor inside the high-voltage pack; GM's Volt bulletin 18-NA-342 lists the matching codes as temperature sensor 4 of nine. P0AE8 is the general circuit code for it, used when the controller finds an electrical fault without classifying it as low, high or erratic. No manufacturer documents this exact code publicly; GM's hybrid tables report the more specific siblings P0AE9 to P0AEC instead. CARB requires temperature inputs of hybrid batteries to be monitored for circuit faults. With one value missing, the controller has a gap in its temperature picture and usually limits charge and discharge power. The sensor sits on a module or sensing board inside the pack, so checks require high-voltage safety procedures.

Likely causes

Poor contact or damaged wire between sensor D and sensing board
Temperature sensor D failed
Fault in the battery controller input stage

Symptoms

  • Hybrid system or check engine warning
  • Reduced electric power and regeneration
  • Further battery sensor codes may be stored

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€150–2,500
Time1–5 h

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

Parts involved

hv battery temp sensor dwiring harnessbms

Related codes

P0AE9P0AEAP0AEBP0AECP0ACAP0BC2

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