P0AE8 code meaning
Hybrid/EV Battery Temperature Sensor D Circuit
Powertrain system Generic code P0Axx codes Check engine light
What P0AE8 means
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.
P0AE8 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0AE8
- Hybrid system or check engine warning
- Reduced electric power and regeneration
- Further battery sensor codes may be stored
Common causes of P0AE8
- Most likelyPoor contact or damaged wire between sensor D and sensing board
- PossibleTemperature sensor D failed
- Less likelyFault in the battery controller input stage
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery temp sensor dWiring harnessBms
What each part of P0AE8 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A | Area: hybrid propulsion. |
| E8 | The exact fault in that area. |
What to do next
- Note P0AE8 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 P0AE8
What does P0AE8 mean?
P0AE8 means "Hybrid/EV Battery Temperature Sensor D Circuit". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P0AE8?
Drive gently and only to a workshop. With P0AE8 the car can go into limp mode (reduced power) to protect itself.
Will P0AE8 fail an emissions test?
Yes, it can. P0AE8 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 P0AE8 to fix?
Difficulty: workshop only. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P0AE8 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.