P0AE9Hybrid/EV Battery Temperature Sensor D Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0AE9 is the plausibility check for battery temperature sensor D, GM's sensor 4: its reading is compared with the other pack sensors. In GM's 2016 and 2019 tables it fails when the value is more than 25 °C away from the average of the others in 50 of 67 samples; the two-mode hybrid tables of 2011 and 2013 use more than 15 °C in 90 of 100; the eAssist table 13OBDG05C allows 8.55 °C after a long module off time; GM's 2018 table uses 20 °C for 5 s within 6.7 s. All are Type B, two trips. Volt bulletin 18-NA-342 counts P0AE9 among sensor codes that set falsely in cold weather and fixes them by reprogramming. Otherwise a drifting sensor or a real hot spot in one module is the likely cause.
- What you may notice
- Malfunction indicator lamp after two trips
- Battery Too Cold message despite mild weather (Volt)
- Reduced charge and electric drive power
- Likely causes
- PossibleOutdated controller software (GM Volt, bulletin 18-NA-342)
- PossibleTemperature sensor D drifting out of tolerance
- RareGenuine local temperature difference in one battery module
- RareIncreased contact resistance in the sensor circuit
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.