2021-2024 Audi A4/S4 Rear Window Reverses Direction TSB

Owners of 2021-2024 Audi A4, A4 allroad, and S4 vehicles may encounter a problem where the rear windows fail to close completely using the one-touch feature. Instead, the window reverses direction immediately upon reaching the upper stop. This behavior indicates a specific software issue within the door module.

This condition, where the Audi A4 rear window reverses, is addressed by Audi Technical Service Bulletin (TSB) 2070094/1, released on April 20, 2023. The TSB outlines a straightforward diagnostic and repair procedure to rectify the underlying software glitch.

Symptoms

Vehicle owners will observe that one or both rear windows cannot be closed using the one-touch feature. The window will reverse direction immediately when it reaches the upper stop, preventing full closure. This is the primary symptom indicating the need for attention to the Audi A4 rear window reverses issue.

Fault Codes / DTCs

When diagnosing this issue, technicians may find the following Diagnostic Trouble Code (DTC) stored intermittently in the left and/or right rear door module (J388 or J389, diagnostic address 00BB or 00BC):

• DTC B14874B: Motor for window regulator excess temperature.

Diagnosis / Trigger Conditions

The root cause of the rear window malfunction is identified as a software issue within the door module. The presence of DTC B14874B confirms that the door module is incorrectly detecting an 'excess temperature' condition for the window regulator motor, leading to the window reversing as a safety measure.

Repair Procedure Summary

To resolve the issue where the Audi A4 rear window reverses, Audi TSB 2070094/1 instructs technicians to perform a power reset of the affected door modules. The procedure involves the following steps:

1. Fuse Removal: Locate fuse carrier C (black) and remove fuses 7 and 11, which supply power to the two rear door modules.
2. Wait Period: Allow two minutes for the modules to fully discharge and reset.
3. Fuse Reinsertion: Reinsert fuses 7 and 11 back into fuse carrier C.
4. Basic Settings Reset: If the basic settings for the window regulator were lost during the power reset, they must be re-established. This can be done using a shop tester or by manually pulling the window regulator switches upwards for approximately two seconds after the windows have been closed.
5. Fault Clearing: Clear all stored fault codes from the vehicle's systems.
6. Re-evaluation: Re-evaluate the window operation to ensure the issue is resolved.

Required Tools or Parts

For diagnostic and repair procedures, technicians will require:

• VAS 6160/VAS 6150: A VAS tester equipped with the current version of ODIS (Windows 10).

Important Warnings

It is crucial to note that this TSB (2070094/1) specifically addresses situations where DTC B14874B is stored. This bulletin does not apply to instances where DTC B148754,