ZN Connection offline

Technical Service Bulletin

Topic 43 "Four-wheel drive: fault" message displayed in instrument cluster on rear-wheel drive vehicles
Market area United States 444 Volkswagen of America, Inc. (6444)

Brand Audi

Transaction No. |2079812/1

Level EH

Status Released for publishing

Release date | Oct 24, 2025

New customer code

Object of complaint Complaint type Position
engine -> engine operation -> Acoustic vehicle warning system soqucres roonect

information, navigation, communication, entertainment -> warning display functionality

symbols

HoT ea ere Deere ste” unetonaty > activates

New workshop code

Object of complaint Complaint type Position

power, vehicle electrical system, data transfer -> in-car application server -
> control module for drive and suspension functions

control modules, services ->

software faulty

Vehicle data

A6 e-tron

Sales types

Type |MY

Brand | Designation} Engine code

Gearbox code

Final drive code

GH* |2025/A

*

*

GH* |2026/A

*

*

Chassis numbers

PR numbers
?:with 1X2

Manufacturer | Filler| Type | Filler} MY|Factory|From /|To Prod from| Prod to
* * GH |* S IA 000000 |031181

* * GH |* R |A 000000 |999999

PR numbers

Documents

Document name

master.xml

ZN Connection offline

Technical Service Bulletin Transaction No.: 2079812/1

43 "Four-wheel drive: fault" message displayed in instrument cluster on rear-wheel

. . Release date: Oct 24, 2025
drive vehicles

Condition

Customer states:

The message “Four-wheel drive: fault” is displayed in the instrument cluster.
Workshop findings:

The vehicle in question is rear-wheel drive (PR number: 1X2) and the message is therefore not correct.

Technical Background
Optimized software for HCP1 control unit (J1312 / diagnostic address 812C).

Production Solution
From production date 09/18/2025 onward.

Service

Please check whether TSB 2079690, 00 Combined software update 03.10.00/C (28.13.01) KD2 is visible for the
vehicle. If this is the case, please perform the software update described in TSB 2079690.

The software update described in TSB 2079690 will be released in stages for the individual vehicle models/markets,
depending on availability.

The combined software update TSB 2079690 may not be available for your vehicle or your market at the current
time.

Please note that no further e-mail notification will occur.

It is recommended to check regularly whether new revisions of TSB 2079690 have been published for other vehicle
groups.

Warranty
Claim Type: * If the vehicle is outside of any warranty, this Technical Service Bulletin is
informational only.

Service Number: 4316

Damage Code: KDO2

Labor Operations: Software update, including connecting battery 0151 0010 See SRT with
charger associated

operations

Fixed rate for software update, including all 0151 0040 130 TU

required preliminary and follow-up work
(including bus sleep cycle, calibration drive,
additional work, and restarting the software
update if flashing is aborted

Claim Comment: As per TSB 2079812/1

All warranty claims submitted for payment must be in accordance with the Audi Warranty Policies and Procedures
Manual. Claims are subject to review or audit by Audi Warranty.

Additional Information

All part and service references provided in this TSB (2079812) are subject to change and/or removal. Always check
with your Parts Department and/or ETKA for the latest information and parts bulletins. Please check the Repair
Manual for fasteners, bolts, nuts, and screws that require replacement during the repair.

©2025 Audi of America, Inc. All rights reserved. The information contained in this document is based on the latest
information available at the time of printing and is subject to the copyright and other intellectual property rights of
Audi of America, Inc., its affiliated companies, and its licensors. All rights are reserved to make changes at any time
without notice. No part of this document may be reproduced, stored in a retrieval system, or transmitted in any form
or by any means, electronic, mechanical, photocopying, recording, or otherwise, nor may these materials be
modified or reposted to other sites, without the prior expressed written permission of the publisher.