Powertrain, generic (extended)

P2D46 Hybrid/EV Battery Pack B Over Temperature

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2D46 extends the pack over-temperature check to a battery that is split into several separately watched sections: section B has run hotter than its protection limit, while section A, on undivided batteries the whole pack, uses P0A7E. No manufacturer documents P2D46 publicly. GM shows how the parent code works: its 2019 table 19OBDG02 takes the hottest module reading and fails above 65 °C in 80 of 100 samples at 100 ms, Type A, so the MIL comes on after one trip. A divided pack would run that comparison per section. CARB asks for monitored battery temperature inputs and a functional check of battery cooling. The car usually cuts charge and drive power until section B cools down.

Likely causes

Restricted coolant or air flow through section B (blocked channel, kinked hose, clogged intake)
Sustained high load or repeated fast charging in hot weather
Temperature sensor in section B reading too high without a circuit fault
Aged modules in section B with raised internal resistance

Symptoms

  • Hybrid or EV system warning and check engine light
  • Reduced electric drive power and regeneration
  • Charging slowed or interrupted

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–4,000
Time1–10 h

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

Parts involved

hv battery pack bbattery thermal managementbattery energy control module

Related codes

P0A7EP2D47P0EDDP0A9CP0C32

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