2022-2023 Audi Brake Noise TSB 2034181/20

Owners of 2022-2023 Audi vehicles, including the Audi e-tron, may experience various brake noises from the front or rear brakes. This Technical Service Bulletin (TSB) 2034181/20, issued on April 7, 2022, provides comprehensive guidance for diagnosing and addressing these concerns. This TSB supersedes an earlier bulletin, Group 46 number 22-27, dated January 31, 2022.

Symptoms

Customers may report hearing a range of brake noises, including:

• "squeal"
• "squeak"
• "grinding"
• "groaning"
• "thumping"
• "creaking"

These noises can originate from either the front or rear brake assemblies.

Important Warning

Note: "DO NOT use this TSB if there is another brake noise TSB applicable to the VIN."

Technical Background: Causes of Brake Noise

Brake noise can stem from several factors. The TSB outlines common causes that technicians should investigate:

• Wear Limits: Brake discs or brake pads are close to or below their wear limit.
• Improper Embedding: New brake pads and/or discs have not been properly embedded after installation.
• Aftermarket Components: Aftermarket pads or discs have been installed.
• Debris: Presence of debris such as small stones, grit, road salt, or sand between the brake disc and brake pad.
• Rust: Discs are covered with rust, which can form when the vehicle has not been driven for a long period of time (as shown in Figure 1 of the TSB).
• Grooved Discs: The brake discs exhibit grooving (as shown in Figure 2 of the TSB).
• Chemical Contamination: Chemical contamination on the braking surface of the brake disc, often due to wheel or tire cleaner being sprayed directly onto the brake disc (as shown in Figures 3 and 4 of the TSB).
• Pad Marks: "Pad marks" on the brake disc resulting from brake pad material transferring to the discs (as shown in Figure 5 of the TSB). This can occur when a vehicle has been parked for long periods in wet or snowy environments.

Diagnosis and Service Procedure

To address an Audi e-tron brake noise concern, technicians should follow a structured diagnostic process:

1. Initial Brake Condition Check: Evaluate the overall condition of the brakes to determine if the noise is caused by any of the issues listed in the Technical Background section. If the noise is not attributed to these causes, proceed with the subsequent steps.
2. Locate the Noise: Accurately determine the location of the brake noise (e.g., left front, front axle, rear axle). An assistant may be needed to listen from inside or outside the vehicle.
3. Record and Document: Obtain a sound or video recording of the noise and complete a questionnaire. Sound recordings should be made using a cell phone with the Audi analysis app (refer to TSB 2051095: 46 Audi frequency analysis). Customer-submitted recordings are also acceptable. Only sound recordings are typically necessary to minimize file size, with videos only sent if critical for understanding conditions. The questionnaire should be filled out as completely as possible.
4. Clean Brake Pads and Discs: This involves a specific procedure:
   • Perform up to five ABS stops from speeds above 50 mph, allowing the brake components to cool for over one minute at speeds greater than 50 mph between each stop.
   • Allow the vehicle to sit for two hours to cool down.
   • Test drive the vehicle again.
5. Technical Assistance Center (TAC) Ticket: If the Audi e-tron brake noise persists after cleaning and re-testing, open a TAC ticket. Include the completed Brakes Acoustic Questionnaire, sound/video recording (preferably from the Audi frequency app), a frequency analysis screenshot (Figure 6 of the TSB), and photos of the affected brake discs and pads (Figures 7 through 11 of the TSB).

Known Brake Noise Frequencies and Solutions

The TSB provides specific inspection and repair suggestions based on the brake system type and the frequency of the noise:

• Brake system ATE-TEVES (with PR codes: 1LF/1LG/1LL/1ZK/1LJ/1LP):

  • 1.6 KHz from front brakes: Inspect front pads.
  • 3.2 KHz/11 KHz from front brakes: Inspect front discs and pads.

• Brake system TRW (with PR codes: 1LA/1LB/1LD/1LT/1ZT/1LJ):

  • 1.6 KHz to 1.7 KHz from front brakes: Inspect front discs.
  • 3.2 KHz from front brakes: Inspect, clean, and lubricate the guide pins in the caliper carrier using anti-seize paste G052560A2.
  • 7.8 KHz from front brakes: Inspect front pads.

Required Tools or Parts

For specific brake system TRW issues, anti-seize paste with part number G052560A2 is required for lubricating guide pins.

Warranty Information

This service is covered under warranty with the following details:

• Claim Type: 110 (up to 12 Months/12,000 Miles).
• Service Number: 4617.
• Damage Code: 0020.
• Labor Operations: Cleaning brake pads and discs (Labor Operation 4617 8099, 70 TU). This includes road tests, submission of an audio file, and questionnaire.
• Diagnostic Time: GFF (No allowance), road test prior to service (No allowance), road test after service (No allowance).
• Claim Comment: As per TSB 2034181/20.

Note that if the vehicle is outside of warranty, this Technical Service Bulletin is for informational purposes only.

Additional Resources

Technicians may need to refer to these additional Technical Service Bulletins:

• TSB 2022584: 46 Brake pulsation diagnostic guidelines.
• TSB 2051095: 46 Audi frequency analysis.

All parts and service references are subject to change. Always consult the latest information from your parts department or ETKA, and the Repair Manual for specific fastener requirements.

NHTSA ID: 10210254