Attachment Bulletin # 910603

Group: 91

Number: 06-03

Date: Feb. 8, 2006

Subject:
Multi Media Interface (MMI), Audio, and Battery Concerns

Model(s):
A8, A8L 2004 --> 2005
A6 2005

Supersedes T.B. Group 91 number 05-09 dated Jun. 16, 2005 due to additional information.

Condition

At ambient temperatures below 40°F, processor failure in the radio can cause any one of the conditions listed below. Another symptom of radio processor failure is waking up of the Media Orientated Systems Transport (MOST) / Can Bus system. This symptom will eventually deplete main battery voltage.

1. MMI is slow to respond.

2. "Radio Not Installed" is displayed in the MMI screen.

3. Poor or intermittent radio reception.

4. Engine will not start.

5. Station list is sporadically completely empty.

6. Intermittently no sound for several minutes (only with radio operation).

Production

New hardware in radio tuner as follows:

^ A6 as of VIN 4F_5N078189.

^ A8, A8L as of VIN 4E_5N012350.

Service








- Obtain radio Part No. (black arrow) and EC No. (white arrows) from radio (located in trunk) and compare to table shown.

If EC Software level is below levels indicated for Model and Part No. in table, perform the following:

- For condition 1, perform steps A and B. If OK, replace radio.

- For condition 2, replace radio.

- For condition 3, perform steps A, B & C. If OK, replace radio.

- For condition 4, perform steps A, B & D. If OK, replace radio.

Tip:

Step C applies only to the A8 and A8L.

Step A:

- Check the MMI, Radio and Battery Manager for DTC's.

- Repair or replace components as necessary.

Step B:

- Perform a ring break diagnosis using VAS 6186 MOST repeater (see Tip below).

Tip:

When performing the ring break diagnosis, follow the literature that is provided with special tool VAS 6186. For additional information on fiber optics, refer to Audi Self Study Program (SSP) 971303: New Data Bus Systems, Fiber-Optic Data Bus.

- Repair or replace components as necessary.

Step C (only applies to A8 & A8L):

A defective Antenna Selection control module -J515- can cause poor radio reception. This can be checked as follows:

- Remove rear headliner / roof frame trim.

- Select AM/FM station where customer has the reception issue.





- Gently push Antenna Selection control module -J515- (black arrow) in the center against the glass using a non-metallic object (e.g. wooden dowel or pen).

^ If Antenna selection control module is faulty, an improvement of the reception quality can be heard.

- Repair or replace component as necessary.

Step D:

- Check charging system and battery condition.

- Repair or replace components as necessary.





When procedure applies to vehicles within the New Vehicle Limited Warranty, use the table.