Engine-Codes - Cadillac - P0AA9 CADILLAC

P0AA9 CADILLAC Code - Hybrid/EV Battery Voltage Isolation Sensing Circuit 1 Low Voltage

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3
Table of contents

|P0AA9 CADILLAC code possible causes

  • Faulty Hybrid/EV Powertrain Control Module 2
  • Hybrid/EV Powertrain Control Module 2 harness is open or shorted
  • Hybrid/EV Powertrain Control Module 2 circuit poor electrical connection

|How is the P0AA9 CADILLAC code repair?

Start by checking 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.

|What is the cost to diagnose the P0AA9 CADILLAC code

Labor: 1.0

The cost to diagnose the P0AA9 CADILLAC code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

|What are P0AA9 CADILLAC code possible symptoms?

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

|What is P0AA9 CADILLAC code meaning?

Vehicles equipped with high voltage storage and propulsion capability are designed with high voltage circuits isolated from the vehicle chassis. If either the positive or negative high voltage Direct Current (DC) circuits or any of the high voltage Alternating Current (AC) phase circuits lose this isolation to the vehicle chassis, one or more Diagnostic Trouble Codes (DTC) may be set.
The Hybrid/EV Powertrain Control Module 2 performs active isolation testing to monitor the internal Hybrid/EV battery pack HV circuits for chassis isolation. The Hybrid/EV Powertrain Control Module 2 switches fixed resistors between the high voltage system and vehicle chassis. The difference between the switched-to-chassis state and the unswitched state is used to calculate a resistance-to-chassis value. The DTC will be set when the Isolation sensor voltage is less than 5 V.

|Need more information with the P0AA9 CADILLAC code?

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|Need help with a P0AA9 CADILLAC code?

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