2021-2023 Audi e-tron Electric Drive Motor Leak TSB

Understanding the Audi e-tron Electric Drive Motor Leak

Audi has released Technical Service Bulletin (TSB) 2073858/3 to address an electric drive motor coolant leak affecting various e-tron models. This TSB, dated October 24, 2024, supersedes previous bulletin Group 93 number 24-22. The issue can manifest as a warning message in the instrument cluster and may lead to the storage of a specific diagnostic trouble code (DTC). This document provides crucial information for owners experiencing an Audi e-tron electric drive motor leak.

Symptoms You Might Notice

Owners of affected Audi e-tron vehicles may observe a "Drive System/Electrical System Malfunction" message appearing in the instrument cluster. This warning can be accompanied by a more specific instruction: "Electrical system: malfunction! Safely stop vehicle". While this message might not always be present during an inspection, it points to an underlying issue with the electric drive system.

Diagnostic Trouble Codes (DTCs)

When diagnosing this condition, technicians may find the diagnostic trouble code (DTC) P0AA600 stored in the Battery manager control module -J840-. This code specifically relates to a Hybrid/EV Battery Voltage System Isolation issue, which in the context of TSB 2073858/3, is often linked to an internal coolant leak in the electric drive motor.

Diagnosis and Trigger Conditions

The primary cause identified in TSB 2073858/3 is an internal coolant leak within the electric drive motor. Technicians will look for signs such as a full coolant drip container or coolant actively leaking from the active chamber on either the front or rear axle. Even an empty drip container can indicate a leak, especially in vehicles with low mileage. A few milliliters of coolant leakage from the resolver cover (Figure 3 in the TSB) is considered normal and not a technical issue, but coolant should not escape from the active chamber bores.

Important Warnings for Owners

Audi has provided several critical advisories within TSB 2073858/3:

• Cooling System Operation: Vehicles should never be operated without a correctly filled cooling system. This is vital for preventing further damage.
• Component Replacement: The power electronics for the electric drive motor do not necessarily need to be replaced if the electric drive motor is leaking. The TSB explicitly states: "In this case, the power and control electronics for electric drive must not be replaced."
• Warranty Coverage: If your vehicle is outside of its warranty period, this Technical Service Bulletin is for informational purposes only.

Repair Procedure Summary

The repair process outlined in TSB 2073858/3 focuses on identifying and sealing the source of the coolant leak. Initially, a thorough check for coolant leaks is performed to localize the source. Technicians are instructed to check the seal on the coolant expansion tank and re-secure it if necessary.

Depending on the diagnosis, the repair may involve replacing the front or rear drive motor, or the power and control electronics for the electric drive. The TSB includes detailed labor operations and damage codes for these potential replacements, such as Service Number 9340 for front electric drive motor replacement, 9346 for rear electric drive motor replacement, and 9350 if power and control electronics are replaced.

Required Parts and Tools

Specific parts and tools for this repair are generally referenced through Audi's electronic parts catalog (ETKA) and repair manual (ELSA). Technicians will consult these resources for fasteners, bolts, nuts, and specific components like the front drive motor, rear drive motor, or their associated power electronics.

Warranty Information

Warranty claims related to this Audi e-tron electric drive motor leak are processed according to the Audi Warranty Policies and Procedures Manual. The TSB specifies various service numbers and damage codes for different repair scenarios. For instance, Damage Code 0050 is used for drive motor replacements, while T055 is used if power and control electronics are replaced. Labor operations include checking for leaks (9340 0199, 9346 0199), replacing drive motors (9340 55xx, 9346 55xx, 9346 56xx for e-tron S), replacing power and control electronics (9350 5599, 9350 5699), charging the battery (2706 8950), and general function checks (0150 0060). Test drives before and after service (0121 0004) are also covered.

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Source: NHTSA ID: 11009977