P0AEB
Hybrid/EV Battery Temperature Sensor D Circuit High.
- Generic
- Powertrain
- Generic code
- Medium severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- A
- AreaHybrid propulsion
- EB
- FaultThe specific fault in that area
What it means
P0AEB means the hybrid or EV battery management system saw the signal from battery temperature sensor 'D' read higher than its valid range, which usually looks like an open circuit or a short to reference voltage. Without a trustworthy temperature reading the system cannot protect the battery properly. Which module or pack position 'D' refers to depends on the vehicle, so check the manufacturer data for your model.
Symptoms
- Hybrid or EV system warning light, or a general warning light, on the dashboard
- Reduced power or limited charging and regeneration
- Battery cooling fan running constantly or not at all
- Reduced electric-only range or the engine running more often on a hybrid
- Poor or slow charging, or charging refused
- Battery temperature reading stuck at an extreme value on a scan tool
Possible causes
- Open circuit or high resistance in the temperature sensor wiring or connector, including corrosion or a loose pinlikely
- Faulty battery temperature sensor (thermistor failed open)likely
- Sensor signal wire shorted to a supply or reference voltagepossible
- Damaged or poorly connected sensor harness inside the battery pack after impact, water ingress or previous repairpossible
- Fault in the battery monitoring or battery management control unit input circuitrare
- Outdated control unit software where the manufacturer has issued a known fix for this coderare
How to diagnose
- Read all stored codes and freeze frame data, and note whether other battery temperature sensor codes are present alongside P0AEB.
- Check live data for all battery temperature sensors and compare sensor D with the others and with ambient temperature; a reading stuck at an extreme value points to a circuit fault.
- Look up the manufacturer data to identify where sensor D is and which connectors serve it.
- Visually inspect accessible wiring and connectors for damage, corrosion, moisture or signs of previous repair, with the HV system made safe according to the manufacturer procedure.
- Only if trained and equipped for high-voltage work, isolate the HV system and test sensor resistance and wiring continuity against specification.
- Check the sensor signal wire for short to voltage and the reference supply and ground at the control unit connector, following the wiring diagram.
- Check for applicable software updates or technical service bulletins for your model.
- Clear the code and road test, rechecking live data to confirm the reading is now plausible and the code does not return.
How to fix
- Repair or replace damaged wiring, and clean or reseat corroded or loose connectors.
- Replace the faulty battery temperature sensor or sensor harness assembly to the manufacturer procedure.
- Repair any short to voltage in the signal circuit.
- Dry out and repair any water ingress affecting the pack harness, with any damaged parts replaced.
- Replace or repair the battery management unit only after wiring and sensor have been proven good.
- Install the latest manufacturer software update if it is a documented fix for this fault.
Can I keep driving?
The car may be driven carefully for a short time, but power and charging may be limited and the battery is not being fully protected. Get it diagnosed soon, and stop driving if there is a burning smell, a high-voltage battery warning, or the battery feels unusually hot.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.