2025 Audi A5/Q5/S5/SQ5 Belt Tensioner Error 8118 TSB

Audi has released Technical Service Bulletin (TSB) 2080352/1 to address a specific issue affecting certain 2025 Audi A5, Q5, S5, and SQ5 models. Owners may encounter an SVM error code 8118, indicating that the reversible belt tensioners cannot be reached or are not displaying correctly in the diagnostic log. This condition is often observed following a service update or after the vehicle's battery has been disconnected.

Symptoms

Owners typically won't experience any immediate driving symptoms or dashboard warning lights related to this condition. Instead, the issue is identified during a service visit or diagnostic scan. The primary symptom is the diagnostic system reporting that the reversible belt tensioners cannot be reached. When configuring software, an additional error, "SDB20F0E", may also appear.

Fault Codes / Error Messages

This issue is primarily identified by specific error codes and messages during diagnostic procedures:

• SVM error code 8118: "Reversible belt tensioners cannot be reached identified in event memory SVM"
• Error SDB20F0E: Appears when configuring software related to this condition.

No relevant DTCs (Diagnostic Trouble Codes) are typically stored in the vehicle's system for this particular problem.

Diagnosis / Trigger Conditions

The 2025 Audi A5 belt tensioner error 8118 is commonly triggered under specific circumstances. Technicians have found that the reversible belt tensioners may no longer be displayed in the diagnostic log after an update is performed using KD packages or following a terminal 30 reset. A terminal 30 reset involves disconnecting the battery, which can cause the control unit for low-voltage power distribution to reactivate various terminal 30 paths at different times. This can result in the reversible belt tensioners receiving power several seconds after the airbag control unit, leading to the described behavior.

Important Warnings

Audi has issued critical advisories regarding this condition:

• "No repairs are necessary at this point. Do not replace any components for this condition since this will not resolve the customer's concern."
• "A terminal 30 reset must not be performed." This is because it can lead to the reversible belt tensioners being powered on later than the airbag control unit, causing the diagnostic issue.
• "It is not necessary to replace the airbag control unit (and the reversible belt tensioners)."

Repair Procedure Summary

To resolve the 2025 Audi A5 belt tensioner error 8118 and ensure the reversible belt tensioners are properly recognized, the following steps are recommended:

1. Switch off the ignition (terminal 15): Ensure the vehicle is completely powered down.
2. Allow the vehicle to enter bus sleep mode: This typically takes approximately 10 minutes, indicated by the selector lever LED turning off.
3. Switch the ignition (terminal 15) on again.
4. Read out the event memory/diagnostic data again: After these steps, the airbag and reversible belt tensioners should then be shown correctly in the diagnostic system.

Additionally, technicians should check whether the responsible reversible belt tensioner control units, as specified in TSB 2080352/1, can be found in diagnostic addresses 062A and 062B. If they are not shown, further work may be required to resolve the issue.

Owner Action

If you own a 2025 Audi A5, Q5, S5, or SQ5 and suspect you are experiencing the "Reversible belt tensioners cannot be reached identified in event memory SVM" error 8118, you should contact your authorized Audi dealership. While no immediate repairs are necessary, and no parts should be replaced for this specific condition, your dealership can create a PSS record through the Pending Service Solutions (PSS) link in Audi Now. Audi is currently reviewing this matter, and a resolution is expected by the end of the second quarter of 2026. Your dealership will be advised of any necessary actions at that time.

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Source: NHTSA ID: 11027369