2015-2026 Audi Brake Squeal Diagnosis TSB

Audi Technical Service Bulletin (TSB) 2051095/8, issued on September 18, 2023, provides guidance for diagnosing brake system noise, specifically Audi e-tron brake squeal, across a wide range of Audi vehicles from model years 2015 to 2026. This bulletin supersedes TSB Group 46 number 22-33 dated June 9, 2022.

The TSB is informational, designed to help technicians accurately identify the frequency of brake-related noises. Understanding the exact frequency is crucial for Audi of America to develop feasible solutions, such as new pad materials, pad geometry, backing plates, spring designs, or balance weights.

Symptoms

The primary symptom addressed by this TSB is brake squeal or other brake system noises. Owners may notice a high-pitched sound when applying the brakes. This noise can vary in intensity and frequency depending on driving conditions.

Important Warnings

Audi explicitly states that "Brake squeal is not a defect." This means that while it is a common customer concern, it is considered a normal result of multiple factors acting on the brake system, rather than a manufacturing flaw.

Furthermore, this TSB is purely informational and "not applicable to any Audi Warranty." Owners should be aware that diagnostic or repair work related to brake squeal may not be covered under warranty, as it's not classified as a defect.

If using an iPhone for the diagnostic app, technicians may encounter an "Untrusted Enterprise Developer" error message. The full message reads: "iPhone Distribution: AUDI AG" has not been trusted on this iPhone. Until this developer has been trusted, their enterprise apps will not be available for use." This is a security feature and needs to be resolved before the app can be used.

Diagnosis Procedure Summary

To diagnose Audi e-tron brake squeal, technicians are instructed to use the Audi Frequency Analysis App. This app allows for precise measurement of brake noise frequencies.

1. Download the Audi Frequency Analysis App:

   • Apple (iOS): Download from the App Store via https://apps.apple.com/us/app/audi-frequency-analysis/id1589055470.
   • Android: Download from Google Play via https://play.google.com/store/apps/details?id=de.audi.frequenzanalyseapp&gl=DE.

2. Resolve iPhone "Untrusted Enterprise Developer" Error: If this error appears, navigate to Phone Settings >> General >> Profiles & Device Management >> Enterprise APP >> Audi AG and select Trust Audi AG.

3. Perform Frequency Analysis:

   • Open the app and select "Record" (Aufnehmen) to begin the frequency analysis. The app can record brake squeal from both inside and outside the vehicle.
   • The app displays the main frequency causing the squeal (e.g., 1.6 KHz or 3.2 KHz) and the noise level in dB. Technicians can move a red scale to identify the main frequency, being mindful of surrounding noises that might obscure the focus.

4. Export Data: After recording, technicians can select the "More" icon, choose the desired audio file, and then select "Exportieren" (Export) to send the file. This audio file can then be attached to a Technical Assistance Center (TAC) case for further review and support.

Required Tools or Parts

The primary tool required for this diagnostic procedure is the Audi Frequency Analysis App, which is a software application available for both Apple iOS and Android devices.

Owner Action

If you are experiencing Audi e-tron brake squeal or other brake noises, it is advisable to contact your authorized Audi service center. While brake squeal is not considered a defect, technicians can use this diagnostic method to understand the specific characteristics of the noise. Be aware that, as per the TSB, this diagnostic work may not be covered under warranty.

NHTSA ID: 10242948