2021-2023 Audi Q8 Rear Suspension Lowering Issue TSB

Audi has released Technical Service Bulletin (TSB) 2059841/2 to address an intermittent issue where the rear suspension lowering function becomes unavailable in certain 2021-2023 Audi Q7, Q8, SQ8, and RS Q8 models. This bulletin, which supersedes TSB Group 43 number 20-39 dated June 17, 2020, provides guidance for technicians on diagnosing and resolving the problem without unnecessary component replacement. Owners experiencing issues with their Audi Q8 rear suspension lowering should be aware of this information.

Symptoms

Owners of affected Audi vehicles may notice that the rear suspension lowering function is intermittently unavailable. This means that when attempting to use the controls to lower the rear of the vehicle, the system does not respond as expected. This can be a frustrating experience, especially when needing to load or unload cargo.

Fault Codes / DTCs

When diagnosing this issue, technicians will typically find one or both of the following Diagnostic Trouble Codes (DTCs) logged in the suspension control module, J775 (address word 0074):

Code	Description
C11B515	Button for high load level, interruption/short circuit to positive
C11B615	Button for low load level, interruption/short circuit to positive

These DTCs specifically point to an electrical issue related to the buttons used for controlling the rear suspension's load level.

Diagnosis and Cause

The technical background for this issue, as described in TSB 2059841/2, is straightforward. The rear suspension lowering function can become sporadically unavailable if the button for lowering the rear suspension is unintentionally operated while the vehicle is in motion. This often happens if objects in the trunk area accidentally press the control button. This unintentional activation during driving can trigger the fault codes C11B515 or C11B615.

Important Warnings

Audi explicitly states a critical instruction for technicians and owners regarding this issue: Do not replace the J775 control module or the button for the rear suspension lowering, or any other component in the vehicle. This warning is crucial as it prevents unnecessary and costly part replacements. The TSB clarifies that replacing these components will not resolve the underlying issue, which is typically related to accidental button presses.

Repair Procedure Summary

The repair for the intermittent Audi Q8 rear suspension lowering issue is relatively simple and does not involve replacing parts. The procedure outlined in TSB 2059841/2 includes two main steps:

1. Explain System Functionality: The technician should explain the functionality of the rear suspension lowering system to the customer. This includes informing them about the possibility of unintentional operation if objects in the trunk area press the control button while driving.
2. Clear DTCs: The technician will then clear any logged DTCs (C11B515, C11B615) from the suspension control module and release the vehicle. No further action or component replacement is typically required.

Owner Action

If you are experiencing intermittent issues with your Audi Q8 rear suspension lowering, and especially if you suspect items in your trunk might be accidentally pressing the control buttons, it is recommended to contact your authorized Audi dealership. They can diagnose the issue, confirm if TSB 2059841/2 applies, and perform the necessary steps to clear the fault codes. Since this is often a simple reset and explanation, it helps avoid unnecessary repairs.

Warranty Information

This service is covered under Audi's warranty for up to 48 months or 50,000 miles. For Certified Pre-Owned (CPO) vehicles, coverage is also provided. If the vehicle is outside of warranty, this Technical Service Bulletin serves as informational guidance for diagnosis and repair.

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Source: NHTSA ID: 10216012