P2D46 code meaning
Hybrid/EV Battery Pack B Over Temperature
Powertrain system Generic code P2Dxx codes Check engine light
What P2D46 means
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.
P2D46 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 10 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2D46
- Hybrid or EV system warning and check engine light
- Reduced electric drive power and regeneration
- Charging slowed or interrupted
Common causes of P2D46
- Most likelyRestricted coolant or air flow through section B (blocked channel, kinked hose, clogged intake)
- PossibleSustained high load or repeated fast charging in hot weather
- PossibleTemperature sensor in section B reading too high without a circuit fault
- Less likelyAged modules in section B with raised internal resistance
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery pack bBattery thermal managementBattery energy control module
What each part of P2D46 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 46 | The exact fault in that area. |
What to do next
- Note P2D46 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2D46
What does P2D46 mean?
P2D46 means "Hybrid/EV Battery Pack B Over Temperature". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P2D46?
Drive gently and only to a workshop. With P2D46 the car can go into limp mode (reduced power) to protect itself.
Will P2D46 fail an emissions test?
Yes, it can. P2D46 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2D46 to fix?
Difficulty: workshop only. A typical repair takes 1 to 10 hours of work. This is a job for a workshop.
Will P2D46 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.