2022-2024 Audi A3, S3, RS 3, Q3 Emergency Call Fault TSB

Audi has issued Technical Service Bulletin (TSB) 91 24 28 2073131/2, superseding previous bulletin 24-73, to address a software-related problem affecting the emergency call system in certain 2022-2024 Audi A3, S3, RS 3, and Q3 models. This bulletin, dated July 17, 2024, provides guidance for diagnosing and resolving instances where the emergency call function displays a fault message.

The core of the problem is a restricted function within the Control Module for Emergency Call and Communication Unit (OCU) -J949-, specifically the OCU3 High variant. This software issue can lead to the system malfunctioning and triggering a diagnostic trouble code (DTC).

Symptoms

Owners of affected Audi vehicles may observe the following symptom related to the emergency call system:

• An "Emergency call fault" message displayed on the instrument cluster, often accompanied by the specific text: "Emergency call function: fault. Function unavailable. Please contact workshop". This indicates a problem with the vehicle's ability to perform emergency calls.

Fault Codes / DTCs

When this issue occurs, technicians will find a specific diagnostic trouble code (DTC) stored in the Control Module for Emergency Call and Communication Unit (OCU) -J949- (address word 0075):

Code	Description	Module
U178500	Control Module for Emergency Call Module and Communication Unit, software error (passive/sporadic)	Control Module for Emergency Call and Communication Unit (OCU) -J949-

This DTC U178500 confirms the software error within the emergency call module.

Important Warnings for Owners and Technicians

Audi has provided critical advisories regarding this issue:

• Parts Replacement: "Parts replacement does not solve this issue. Claims for replaced parts will be subject to review." This means that replacing the OCU -J949- module will not fix the underlying software problem and is not covered under warranty if attempted.
• Re-occurrence: "The complaint may re-occur. If the complaint occurs again, please repeat the procedure above." Owners should be aware that while the software update is intended to be a permanent fix, in rare cases, the fault could reappear, requiring a repeat of the diagnostic and repair process.

Diagnosis

When an Audi S3 emergency call fault U178500 is reported, workshop findings typically involve the logging of DTC U178500 in the Control Module for Emergency Call and Communication Unit (OCU) -J949-. The diagnostic process involves confirming the presence of this DTC and the associated instrument cluster message.

Repair Procedure Summary

The permanent solution for the Audi S3 emergency call fault U178500 is a software update for the Control Module for Emergency Call and Communication Unit (OCU) -J949-. This update is designed to rectify the software error that causes the emergency call system malfunction. The software update for service was planned to be available not before week 23/25.

Technicians are instructed to perform the suggested ODIS Test Plan, specifically "Check OCU control module configuration." After completing the repair, it is crucial to ensure that the emergency call LED is illuminated green before releasing the vehicle to the customer. This confirms the system is functioning correctly.

Warranty Information

This repair, outlined in TSB 2073131/2, 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, requiring verification of ownership. If the vehicle is outside of its warranty period, this Technical Service Bulletin serves as informational guidance only, and costs may apply. The service number for this procedure is 9170, with a damage code of 0039. Claims should be submitted as per TSB 2073131/2 and must adhere to the Audi Warranty Policies and Procedures Manual.

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Source: NHTSA ID: 11005931