2021 Audi A6, A7, A8, e-tron Front Seat Belt Twisting

Symptoms

Owners of affected Audi vehicles may notice that one or both of the front seat belts are twisted. This can make the seat belt uncomfortable to wear or difficult to retract properly.

Technical Background

According to Audi, the seat belt webbing can become twisted as it passes through the deflector of the seat belt height adjuster. This issue is primarily attributed to the "seat belt park function" found in the reversible seat belt tensioners. When the seat belt is unbuckled and retracts, a slight twist can occur. If this twist reaches the deflector and the "seat belt park function" then activates, the twist can be pulled past the deflector, resulting in a fully twisted seat belt.

Audi implemented a production solution with modified deflector guides for the A6, A7, A8, and Audi e-tron quattro models starting in the third quarter of 2020. For the Q8, modified seat belts were introduced in production beginning December 2019.

Repair Procedure Summary

To address the Audi e-tron seat belt twisted issue, technicians will perform the following steps:

1. The upper B-Pillar trim on the affected side of the vehicle will be removed, following the repair manual instructions.
2. The bolt securing the seat belt deflector will be removed. It is important to note that the seat belt itself does not need to be removed for this repair.
3. The old plastic belt guide will be carefully detached from the steel deflector using a thumb, starting from the bolt hole and pressing out the lower section. Technicians are advised not to use sharp objects to prevent damage to the seat belt webbing.
4. With the old belt guide removed, the seat belt webbing will be manually turned to correct any twist.
5. A new, modified belt guide will be installed. For the front driver side, part number 4K8 857 799 is used, and for the front passenger side, 4K8 857 800 is used. Installation begins by engaging the guide at the deflector metal tab.
6. The new guide is then pushed into the bolt hole until its plastic retainers audibly snap into place.
7. The technician will inspect the front and back of the deflector to ensure the guide's locking tabs are correctly secured.
8. The seat belt deflector will be reinstalled at the height adjuster.
9. The seat belt will be fully extended and retracted to confirm proper function.
10. Finally, the B-Pillar trim will be reinstalled.

For Q8 models, the procedure involves ordering and replacing the entire affected front seat belt assembly if twisting is the concern. Non-modified seat belts can be used for other issues.

Required Tools or Parts

To perform this repair, specific modified parts are required:

• Relay fitting, left front (for A6, A7, A8, and Audi e-tron quattro): Part Number 4K8857799 (Quantity: 01 as needed)
• Relay fitting, right front (for A6, A7, A8, and Audi e-tron quattro): Part Number 4K8857800 (Quantity: 01 as needed)

For Q8 models, the following three-point automatic seat belt part numbers (old superseded by new) are listed:

• 4M8857705* superseded by 4M8857705C*
• 4M8857706* superseded by 4M8857706C*
• 4M8857705A* superseded by 4M8857705D*
• 4M8857706A* superseded by 4M8857706D*
• 4M8857705B* superseded by 4M8857705E*
• 4M8857706B* superseded by 4M8857706E*
• 4ML857705* superseded by 4ML857705A*
• 4ML857706* superseded by 4ML857706A*

Fasteners, bolts, nuts, and screws may also be needed as per the repair manual.

Warranty Information

This repair is covered under Audi's warranty for up to 48 months or 50,000 miles, whichever comes first. For Certified Pre-Owned (CPO) vehicles, the claim type is G10. If the vehicle is outside of warranty coverage, this Technical Service Bulletin is for informational purposes only, and the repair cost would be the owner's responsibility.

The Service Number for this TSB is 6913, and the Damage Code is 0010. Labor operations vary depending on the number of belts modified and the specific model:

• Modify 1 front belt: Labor Operation 6911 4999 (40 TU for A6 and A7 family; 50 TU for A8, Audi e-tron quattro, and Audi e-tron Sportback).
• Modify 2 front belts: Labor Operation 6911 5099 (70 TU for A6 and A7 family; 90 TU for A8; 80 TU for Audi e-tron quattro and Audi e-tron Sportback).
• Q8 Only - Remove and install 1 belt: Labor Operation 6911 1900.
• Q8 Only - Remove and install 2 belts: Labor Operation 6911 2000.

Diagnostic time (GFF 0150 0000 for Q8 Only) has a maximum of 50 TU. Road tests before and after the service procedure are not allowed additional time (0 TU).

Important Warnings

• Do not use sharp objects when removing the old belt guide, as this can damage the seat belt webbing.
• This repair should only be performed on the side of the vehicle where the seat belt is affected.
• For Q8 models, only order modified seat belts if the concern is twisting. For other issues, non-modified seat belts can be used.

NHTSA ID: 10193930