2015-2026 Audi Vehicles Brake Noise TSB 2034181/24

Owners of 2015-2026 Audi vehicles may experience various types of brake noise, including squealing, squeaking, grinding, groaning, thumping, or creaking from either the front or rear brakes. This Technical Service Bulletin (TSB) 2034181/24, superseding TSB 23-41 dated February 7, 2023, provides a comprehensive guide for diagnosing and resolving these issues.

Technical Background

Brake noise can stem from several common causes. These include brake discs or pads being at or below their wear limit, new brake components not being properly embedded after installation, or the presence of aftermarket pads or discs. Debris like small stones, grit, road salt, or sand lodged between the brake disc and pad can also generate noise.

Other factors contributing to brake noise involve the condition of the discs themselves. Rust can form on discs when a vehicle has been parked for extended periods, as shown in Figure 1 of the TSB. Discs can also become grooved (Figure 2), or suffer from chemical contamination on the braking surface due to wheel or tire cleaner being sprayed directly onto them (Figures 3 and 4). Additionally, "pad marks" (Figure 5) can appear on the brake disc from pad material transfer, especially after long parking periods in wet or snowy conditions.

Important Warnings

Owners and technicians should be aware of specific warnings outlined in this TSB:

• DO NOT use this TSB if there is another brake noise TSB applicable to the vehicle's VIN. Always refer to the Audi Brake systems brochure for additional information.
• DO NOT alter the brake pads when performing the cleaning procedure.

Diagnosis and Repair Procedure

Addressing brake noise in your Audi involves a systematic approach to identify and resolve the underlying cause. This TSB outlines a detailed service procedure for technicians.

Initial Assessment

First, the overall condition of the brakes must be checked to determine if the noise is related to any of the common causes listed in the technical background. If the noise is not attributed to these initial causes, further diagnostic steps are required.

Noise Location and Recording

It is crucial to 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 to pinpoint the exact source. Technicians are required to obtain a sound or video recording of the noise, preferably using the Audi analysis app (refer to TSB 2051095: 46 Audi frequency analysis). Customer-submitted recordings are also acceptable. The recording should clearly identify the noise, and a comprehensive questionnaire must be filled out.

Brake Cleaning Procedure

If the noise persists, a thorough cleaning of the brake pads and discs is performed:

1. ABS Stops: Perform up to five ABS stops from speeds above 50 mph, ensuring to allow brake components to cool for at least one minute at speeds greater than 50 mph between each stop.
2. Cool Down: Let the vehicle sit for two hours to cool down completely.
3. Manual Cleaning: Manually clean all brake components, removing brake dust from springs, retaining clips, pistons, calipers, and pins. All contact points between pads, clips, and calipers should be cleaned and lubricated with the correct paste, as specified in ELSA.
4. Test Drive: Conduct another test drive.

If the noise is still present after these steps, a Technical Assistance Center (TAC) ticket must be opened. This ticket should include the completed Brakes Acoustic Questionnaire, the sound or video recording, and a screenshot of the frequency analysis (Figure 6).

Specific Frequency Analysis and PR Codes

The TSB also provides reference information for vehicles with similar brake systems, categorizing known brake noise frequencies and repair suggestions based on PR codes:

• Brake system ATE-TEVES (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 (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 and, if needed, suggest to 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 and Parts

Technicians will utilize the Audi analysis app (TSB 2051095) for sound recordings. Specific lubrication paste, as detailed in ELSA, is required for brake component contact points. For TRW brake systems experiencing 3.2 KHz noise, anti-seize paste G052560A2 is recommended for caliper guide pins. Additionally, this TSB references TSB 2022584 for "46 Brake pulsation diagnostic guidelines" and TSB 2051095 for "46 Audi frequency analysis" as necessary supporting documents.

Warranty Information

For eligible vehicles, the warranty claim type is 110, covering up to 12 months or 12,000 miles. If the vehicle is outside of warranty, this Technical Service Bulletin is for informational purposes only. The service number is 4617, and the damage code is 0020. Labor operations for cleaning brake pads and discs (code 4617 8099) include road tests, audio file submission, and questionnaire completion, with an estimated time unit of 70 TU.

NHTSA ID: 10242942