2021-2023 Audi e-tron Electric Motor Leak TSB

Symptoms

Owners of affected 2021-2023 Audi e-tron vehicles may experience the following symptoms related to an Audi e-tron electric motor leak:

• A warning message, "Drive System/Electrical System Malfunction", appears in the instrument cluster. This message may not always be present during inspection.
• During a workshop visit, an internal coolant leak may be detected. This is indicated by a full coolant drip container or coolant actively leaking from the active chamber on the front or rear electric drive motor.
• The coolant drip container may be overflowing.
• Coolant may be leaking from the active chamber, even if the drip container appears empty, particularly in vehicles with low mileage.

Fault Codes / DTCs

When an Audi e-tron electric motor leak is present, the following Diagnostic Trouble Code (DTC) may be stored in the Battery manager control module -J840- (address word 008C):

Code	Description	Module
P0AA600	Hybrid/EV Battery Voltage System Isolation	Battery manager control module -J840-

Diagnosis and Trigger Conditions

Diagnosis for the Audi e-tron electric motor leak involves confirming the presence of the "Drive System/Electrical System Malfunction" message and identifying the source of any coolant leaks. Technicians will check the coolant drip containers and active chambers on both the front and rear axles for signs of leakage. It is crucial to differentiate between minor seepage and significant leaks.

Only if specific conditions are met can it be assumed that the electric drive motor is damaged due to an internal coolant leak. A few milliliters of coolant leakage from the resolver cover is generally not considered a technical issue. However, no coolant should escape from the bores of the active chamber.

Important Warnings

Owners and technicians should be aware of critical advisories:

• "Vehicles should never be operated without a correctly filled cooling system."
• "The power electronics must not be replaced if the electric drive motor is leaking." This indicates that the electric drive motor itself is the primary concern, not necessarily the power electronics.

Repair Procedure Summary

The repair for an Audi e-tron electric motor leak involves a thorough inspection and, if necessary, replacement of affected components. The general procedure includes:

1. Coolant Leak Check: Technicians will meticulously check for coolant leaks and pinpoint their exact source.
2. Expansion Tank Seal: If an internal coolant leak is confirmed, the seal on the coolant expansion tank should be checked and re-secured.
3. Component Replacement: If the electric drive motor is determined to be damaged due to an internal coolant leak, it may require replacement. Depending on the specific findings, this could involve replacing the front drive motor, rear drive motor, or both rear electric drive motors (for e-tron S models).
4. Power and Control Electronics: In some cases, the power and control electronics for the electric drive may also need replacement, particularly if they are affected as a group. This must be billed separately according to warranty accounting instructions.
5. High-Voltage System Management: The high-voltage system must be deactivated and reactivated as part of the repair process.
6. Battery Charge and Diagnostics: The vehicle battery will be charged, and Guided Fault Finding (GFF) will be performed.
7. Test Drive: A test drive is required after the service procedure to ensure proper function and confirm the resolution of the Audi e-tron electric motor leak.

Owner Action

If your 2021-2023 Audi e-tron or e-tron Sportback displays a "Drive System/Electrical System Malfunction" warning or you suspect an Audi e-tron electric motor leak, it is recommended to contact an authorized Audi service center immediately. They can perform the necessary diagnostics and repairs as outlined in TSB 2073858/6.

Warranty coverage for this repair depends on whether the vehicle is still within its warranty period. If the vehicle is outside of any warranty, this Technical Service Bulletin serves as informational guidance for repairs.

Source: NHTSA manufacturer communication 11013739.