P0A9E Possible Causes
- Faulty HV battery assembly (HV battery temperature sensor)
- HV battery assembly harness is open or shorted
- Poor electrical connection in HV battery assembly circuit
- Faulty battery intelligent unit
What Does It Mean?
How to Fix Code P0A9E
Check the “possible causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
P0A9E Possible Symptoms
Illuminated engine light (or service engine soon warning light)
P0A9E Meaning
Battery temperature sensors are provided at 3 locations in the HV battery. The thermistor resistance, built into each battery temperature sensor, varies according to HV battery temperature changes. The lower the battery temperature, the higher the thermistor resistance. Conversely, the higher the temperature, the lower the resistance. The battery intelligent unit uses the battery temperature sensors to detect HV battery temperature and sends the detected value to the power management control ECU. Based on this detection result, the power management control ECU controls the fan motor. (The fan motor starts when the HV battery temperature exceeds a predetermined level.)