2021-2023 Audi e-tron Electric Motor Coolant Leak

Symptoms of an Audi e-tron Electric Motor Leak

Owners of 2021-2023 Audi e-tron vehicles may experience various symptoms indicating an Audi e-tron electric motor leak. The most prominent sign is a warning message appearing in the instrument cluster.

Common symptoms include:

• An instrument cluster message stating: "Electrical system: malfunction! Safely stop vehicle". This critical warning advises immediate attention.
• Unusual noises and vibrations from the electric drive system, such as jerking, vibrating, general noise, or pinging sounds.
• Functionality issues with the electro-drive mode, which may manifest as misfires, a complete loss of function, or the system failing to switch on or activate.
• Visible leaks, potentially indicating that the vehicle is "not watertight".
• Coolant leaks observed from the active chamber on either the front or rear axle, or an overflowing/empty coolant drip container.

Fault Codes (DTCs)

When an Audi e-tron electric motor leak occurs, technicians may find specific diagnostic trouble codes (DTCs) stored in the vehicle's systems. The primary DTC associated with this issue is:

• P0AA600: This code, mentioned in the TSB topic, is linked to the electric motor leaking.
• "Hybrid/EV Battery Voltage System Isolation": This fault is stored in the Battery Manager Control Module -J840- (address word 008C).

Diagnosis and Trigger Conditions

Diagnosing an Audi e-tron electric motor leak involves a thorough inspection and confirmation of specific conditions. A damaged electric drive motor due to an internal coolant leak can be assumed if:

• The "Hybrid/EV Battery Voltage System Isolation" DTC is stored in the Battery Manager Control Module -J840-.
• An internal coolant leak is identified during a workshop visit. This might be indicated by a full coolant drip container or coolant actively leaking from the active chamber on the front or rear axle of the electric drive motor.

Technicians will also check the seal on the coolant expansion tank and re-secure it if necessary. They will inspect whether the drip container is overflowing or empty, as both conditions can point to a leak from the active chamber, especially in vehicles with low mileage.

Important Warnings for Owners

Audi has issued specific warnings regarding the Audi e-tron electric motor leak:

• "Vehicles should never be operated without a correctly filled cooling system." This emphasizes the importance of addressing coolant issues promptly to prevent further damage.
• "The power electronics must not be replaced if the electric drive motor is leaking." This advises against unnecessary repairs, ensuring that the correct component is addressed.
• "If the vehicle is outside of any warranty, this Technical Service Bulletin is informational only." Owners of vehicles no longer under warranty should be aware that repair costs may apply.
• "If the power and control electronics for electric drive must be replaced as a group, then this must be billed separately (see warranty accounting instructions)." This clarifies billing procedures for complex repairs.

Repair Procedure Summary

The repair for an Audi e-tron electric motor leak focuses on identifying and sealing the source of the coolant leak, potentially involving electric motor replacement.

1. Coolant Leak Check: Technicians will first check for and localize the source of the coolant leak. This includes inspecting the coolant expansion tank seal and re-securing it if needed.
2. Leak Source Identification: The leak will be traced to determine if it originates from the active chamber of the front or rear electric drive motor.
3. Electric Motor Replacement: Depending on the location and severity of the leak, the affected electric drive motor (front or rear) may need to be replaced. For e-tron S models, both rear axle electric drive motors might require replacement.
4. High-Voltage System Management: The high-voltage system will be deactivated and then reactivated as part of the repair process.
5. Battery Charging: The vehicle's battery will be charged.
6. Diagnostic Protocol (GFF): A guided fault finding (GFF) diagnostic protocol will be performed.
7. Test Drives: Test drives are required both before and after the service procedure to confirm the issue and validate the repair.

Owner Action

If your 2021-2023 Audi e-tron exhibits any of the symptoms described, such as the "Electrical system: malfunction! Safely stop vehicle" warning or unusual noises, it is crucial to contact an authorized Audi service center. Provide them with details of the symptoms and mention the potential for an Audi e-tron electric motor leak and DTC P0AA600. While the TSB provides guidance for technicians, it is informational for vehicles outside of warranty, meaning repair costs might not be covered. Prompt diagnosis and repair are essential to prevent further damage to the electric drive system.

---

Source: NHTSA ID: 11015759