2022-2024 Audi e-tron GT Brake System Software Update TSB 49A4

Owners of 2022-2024 Audi e-tron GT and RS e-tron GT vehicles may notice unusual operating noises from the hydraulic unit or experience higher-than-normal brake pedal travel, particularly at very low speeds. This condition, which can be an annoyance, is addressed by Audi through a proactive software update and brake system service outlined in Technical Service Bulletin 49A4.

This bulletin, originally published on March 21, 2024, and revised on April 9, 2024, provides updated work procedure information for the 49A4 UPDATE.

Symptoms

If you own a 2022-2024 Audi e-tron GT or RS e-tron GT, you might experience the following:

• Loud operating noises from the hydraulic unit of the brake system.
• Higher-than-usual brake pedal travel at very low vehicle speeds.

These symptoms indicate that your vehicle may require the brake system software update detailed in TSB 49A4, which aims to resolve the Audi e-tron GT brake noise and pedal travel concerns.

Fault Codes / DTCs

After the software update, technicians may find a specific fault code logged in the vehicle's system:

• C10E1F2: "Parking brake motor position not plausible"

This fault code must be addressed as part of the repair procedure, typically by performing a specific test plan within the diagnostic system.

Diagnosis / Trigger Conditions

To determine if your Audi e-tron GT brake noise issue is covered by this update, an authorized Audi dealer will check the Elsa Campaign/Action Information screen for the 49A4 code. This code must appear as "open" on the day of repair to confirm vehicle eligibility. The procedure is only valid for vehicles still within their New Vehicle Limited Warranty.

Important Warnings for Owners

Audi has issued several critical warnings and instructions related to this update:

• No Consumer Notification: Audi is NOT notifying consumers directly about this update. Owners must proactively seek this information or inquire with their dealer.
• Warranty Claims: A warranty claim may not be reimbursed if the SVM Process is not completed in its entirety, as the database needs to receive the update confirmation response.
• Safety Recalls First: All open Safety Recalls must be completed prior to performing this campaign.
• Radiator Fan Warning: During the update process, the "Radiator Fan(s) may cycle ON high speed during the Update Process! There is a serious risk that personal injury may result if contact is made with spinning fan blades. Keep hands and all objects away from Radiator Fan(s) during Update Process!"
• GFF Usage: Technicians are instructed to "DO NOT USE Guided Fault Finding (GFF) to perform this flash." Using GFF will prolong the process, and requests for additional time will not be considered.
• Diagnostic Tester Power: "Under no circumstances should the tester be used on battery power alone during the software update." Failure to comply can lead to tester powering off and control module damage.
• Connection Type: Performing a software update using Bluetooth or WiFi connections increases the risk of losing connection and damaging the control module. It also increases the time required. Requests for additional time or parts will be denied if the GFF log shows the update was performed using Bluetooth or WiFi.
• Unattended Bleeding: "DO NOT leave the vehicle unattended while performing the brake fluid flush procedures! Failure to follow these steps may result in excessive brake fluid usage."
• MMI Warnings During Bleeding: "While performing brake bleeding steps, there will be several warnings that appear in the instrument cluster and MMI, these can be ignored."
• Do Not Interrupt Bleeding: During the NX6 brake booster and service bleeding test plans, if the "Status" field shows "False result" or "Result: Unknown status," this is normal. Technicians are warned, "Do not press the complete/continue button! If used, the test plan will fail." The test plan will automatically continue once conditions are met.

Repair Procedure Summary

The repair involves two main sections: a brake electronics software update and a comprehensive brake system bleeding procedure. The campaign code for this update is 49A4.

Brake Electronics Software Update

1. Preparation: Ensure the ODIS software is fully updated, a battery charger is connected to maintain vehicle battery voltage above 12.5 volts, screen saver and power saving settings are off, and the VAS Diagnostic Tester is plugged in with power adapters and connected via a USB cable (not Bluetooth or WiFi).
2. Software Flash: The selector lever must be in 'P'. Use operating mode 'FLASH'. Select "SVM – Code Input" and enter the SVM code 49A4A144. Follow the on-screen prompts.
3. Parking Brake Initialization: If the MMI displays the message "Electromechanical parking brake: not in position" along with "Please press the brake pedal and start the position detection function. This can also be done later by going to Vehicle > Settings & Service > Electromechanical parking brake," follow the on-screen steps to detect the parking brake position.

Brake System Bleeding

1. DTC Check: After the SVM update, scan the vehicle using GFF. If fault code C10E1F2 ("Parking brake motor position not plausible") is present and cannot be cleared, perform the test plan "0003 - Brake Button Initiation" through guided functions of DA 0003. Select option #1 for "Perform complete basic setting" and follow prompts. When asked if rear brake rotors or pads were replaced, select "No".
2. Conventional Bleeding: Perform conventional bleeding of the brakes according to the ELSA Repair Manual (Chassis > Brake System > 47 Hydraulic Components > Hydraulic System > Hydraulic System, Bleeding).
3. NX6 Brake Booster Bleeding: Bleed the NX6 brake booster using the ELSA repair manual and ODIS test plan "0023 - Brake Boost / brake bleeding" (DA 0023). Note that "Status: False result" and "Result: Unknown status" are normal during this process.
4. Service Bleeding: Perform the service bleeding procedure using the ELSA repair manual and ODIS test plan "0003 - Service Bleeding" (DA 0003). Again, "Result: Unknown status" is normal.
5. Finalization: After all bleeding steps, perform a bus sleep on the vehicle by disconnecting the diagnostic tester, removing the key, locking the vehicle with the remote for 5 minutes. Then, erase the fault memory by exiting the GFF session.

Required Parts and Tools

To perform this update and brake system service, specific parts and specialized tools are required:

Parts

• Brake Fluid: Up to 4.5 liters of B 000750S0 (any DOT 4 brake fluid listed in Parts on Command can be used).

Special Tools

• Battery Tester/Charger: Capable of a minimum 90 Amp continuous supply.
• Diagnostic Tester: VAS6150X/VAS6160X (or equivalent).
• Brake Filling and Bleeding Equipment: VAS6860 (or equivalent).
• Brake Bleeding Tool Set: VAS6564 (or equivalent).
• Wrench - Brake Bleeder Set: VAS5519 (or equivalent).

Warranty Information

Audi dealers can claim this repair under warranty. The Service Number for this campaign is 49A4, with a Damage Code of 0099 and Parts Vendor Code 002. Claim types are 7 10 for sold vehicles and 7 90 for unsold vehicles. The causal indicator is marked as causal labor.

Labor Operations and Time Units:

• 0151 00 10: Software update (setup + battery charger) - Time Units: SEE ELSA
• 0151 00 60: Perform Software update - Time Units: Time stated on diagnostic protocol
• 0150 00 60: GFF/Guided functions (perform necessary test plans) - Time Units: Time stated on diagnostic protocol
• 0150 00 99: Bus sleep procedure - Time Units: 10
• 4701 07 50: Brake system bleed (initial bleed procedure, claim only once) - Time Units: SEE ELSA
• 4701 07 70: Brake system bleed (additional bleed procedures, can be claimed up to 2 times) - Time Units: SEE ELSA

Dealers are instructed to submit claims as soon as possible and attach an Elsa screen print showing the action as "open" on the day of repair. If a customer refuses the work or the vehicle is outside warranty parameters, U.S. dealers submit through Audi Warranty Online under Campaigns/Update, while Canadian dealers upload the repair order to Audi WIN/Operations/Campaign Closure.

NHTSA Source: TSB 49A4, Audi of America, Inc.