2021-2022 Audi e-tron Brake Squeal Analysis TSB

Understanding Audi Brake Squeal

Brake squeal is a frequent noise complaint from vehicle owners, but Audi clarifies that it is a normal outcome of multiple factors interacting within the brake system. It is not considered a defect. This Technical Service Bulletin (TSB) 2051095/4, issued on February 10, 2021, is informational. It supersedes TSB Group 46 number 19-05, dated March 14, 2019, and aims to assist technicians in identifying the specific noise frequencies associated with brake system concerns, particularly brake squeal.

Knowing the exact frequency of the brake squeal allows Audi of America to better understand the issue and explore potential solutions, such as new pad materials, pad geometry, backing plates, or spring designs. This process helps ensure that any future developments are well-informed.

What is the Audi Frequency Analysis App?

The Audi Frequency Analysis App is a specialized tool developed to help technicians record and analyze brake system sounds. This application allows for the precise measurement of noise frequencies, which is crucial for diagnosing and addressing brake squeal. The app can be used on both iOS and Android devices, providing flexibility for workshop use.

How to Use the Audi Frequency Analysis App

Technicians can download and utilize the Audi Frequency Analysis App by following a specific procedure:

1. Access the App Shop: Navigate to the Audi B2B App Shop online at https://b2bappshop.audi.de.
2. Sign In: Log in using your Global (GeKo) User-ID and Password. This ensures secure access to the application.
3. Select Device Type: Choose between iOS or Android based on the device being used for the analysis.
4. Install the App: Click "Install" to download and set up the "Frequenzanalyse" app on the device.
5. Record Brake Squeal: Once installed, open the app and select the "Record" (Aufnehmen) function to begin capturing brake noise. Recordings can be made from either inside or outside the vehicle, depending on the conditions that best reproduce the 2021-2022 Audi e-tron brake squeal.
6. Analyze Frequencies: The app displays a frequency analysis, allowing technicians to identify the main frequency causing the squeal. Examples provided in the TSB show typical brake squeal frequencies at 1.6 KHz and 3.2 KHz. It's important to be aware that surrounding noises can sometimes mask the primary frequency.
7. Manage Recordings: The app also offers functions to "Play" (Abspielen), "Cut" (Schneiden), and "Export" (Exportieren) recorded audio files.
8. Export for TAC Case: To share the analysis, technicians can export the audio file from the app and attach it to a Technical Assistance Center (TAC) case. This provides Audi with valuable data for further investigation and solution development.

Important Warnings for App Installation

During the installation process, technicians may encounter specific error messages depending on their device. It's crucial to address these correctly to ensure the app functions properly.

• iPhone Users: If you receive the "Untrusted Enterprise Developer" error message, you must manually trust the Audi AG developer profile. To do this, go to "Phone Settings" >> "General" >> "Profiles & Device Management" >> "Enterprise APP" >> "Audi AG" >> and then select "Trust Audi AG". Until this step is completed, the enterprise apps will not be available for use.
• Android Users: If you see a warning stating "This type of file can harm your device. Do you want to keep Waveform-release-1.9-sign.apk anyway?", select "OK" to proceed with the installation.

What Owners Should Know

This Technical Service Bulletin is primarily for technicians and provides a tool for analysis rather than a direct repair procedure for the 2021-2022 Audi e-tron brake squeal. As stated in the TSB, brake squeal is not considered a defect. Therefore, this informational bulletin is not applicable to any Audi Warranty claims. If you experience persistent brake noise, discuss it with your authorized Audi service center, who can use this tool to provide detailed diagnostic information to Audi.

Source: NHTSA ID 10187349