Engine-Codes - Generic - P0A9D

P0A9D - Hybrid Battery Temperature Sensor 'A' Circuit Low

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

P0A9D Possible Causes

  • Faulty HV Battery Assembly (HV battery temperature sensor)
  • HV Battery Assembly harness is open or shorted
  • HV Battery Assembly circuit poor electrical connection
  • Faulty Battery smart unit

How do I fix code P0A9D?

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's pins.

Cost of diagnosing the P0A9D code

Labor: 1.0

The cost of diagnosing the P0A9D code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P0A9D Meaning

The battery temperature sensors are provided at 3 locations of the HV battery. The resistance of the thermistor, which is built into each battery temperature sensor, varies in accordance with changes in the HV battery temperature. The lower the battery temperature, the higher the thermistor resistance. Conversely, the higher the temperature, the lower the resistance. The battery smart unit uses the battery temperature sensors to detect the HV battery temperature, and sends the detected value to the power management control ECU. Based on the results of this detection, the power management control ECU controls the blower fan. (The blower fan starts when HV battery temperature rises above a predetermined level.)

P0A9D More Information

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Information for specific makes

  • P0A9D BUICK Hybrid/EV Battery Temperature Sensor 1 Circuit Low Voltage
  • P0A9D CADILLAC Hybrid/EV Battery Temperature Sensor 1 Circuit Low Voltage
  • P0A9D CHEVROLET Hybrid/EV Battery Temperature Sensor 1 Circuit Low Voltage
  • P0A9D GMC Hybrid/EV Battery Temperature Sensor 1 Circuit Low Voltage

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