Technical Service Bulletin
91 Bluetooth call quality issues for caller on other end of call
91 14 20 2027718/6 January 3, 2014. Supersedes Technical Service Bulletin Group 91 number 13-11 dated
October 31, 2013 for reasons listed below.
Model(s)

Year

VIN Range

Vehicle-Specific Equipment

2011-2013

A6/A7

All

Bluetooth Hands-Free Calling

2011-2013

A5 CAB

All

Bluetooth Hands-Free Calling

2011-2013

TT

All

Bluetooth Hands-Free Calling

Condition
REVISION HISTORY
Revision

Date

Purpose

6

-

Revised Service (Added diagnostic step to reinstall non-damaged microphones)

5

10/31/2013

Revised Service (Added note to call TAC for certain repairs)
Revised Required Parts and Tools (Changed quantity)

4

6/11/2013

Revised Service (Clarified information)
Revised Warranty (Updated Diagnostic Time)
Revised header data (added model year)

3

11/12/2012

Revised Warranty (Adjusted TUs)

2

8/6/2012

Revised Service

1

10/25/2011

Original publication

When the driver uses the Bluetooth hands-free telephone system to make a call, the listener on the other end
cannot clearly understand the driver. The driver’s voice sounds muffled, as if it is being heard from under water.

Technical Background
The microphone seal is damaged during installation into the roof module.

Production Solution
Improved microphone installation procedure and optimized microphone seal staring with January 2012 vehicle
production. Microphones with improved seals are at the 03S level or greater.
© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin
Service
Tip: This bulletin does not allow for replacement of the microphones unless there is physical damage found
to the rubber seal on the end of the microphone. Because there has been no hardware optimization to the
microphone, replacing a microphone that is not damaged will not improve the sound quality.
Confirm that the sound quality issue is not due to the phone or phone service provider:
1. Ensure that the customer’s phone is an Audi-approved Bluetooth device by checking the list located at
http://microsites.audiusa.com/ngw/12/experience/bluetooth/index.html.
2. Before making any repairs, road test the vehicle at a minimum speed of 45 mph with the top up (if applicable)
and all windows closed.
3. During the road test, verify the call quality issue by making a Bluetooth call to someone at the workshop. Make
sure that the same person will be available to answer another call after any repairs are made so that the call
quality improvement can be verified.
4. If no call quality issues are confirmed during the road test, end all analysis. The issue is most likely due to the
customer’s phone and/or service provider, which can be demonstrated to the customer by using a different
paired phone with a different service provider. In addition, it is normal to have a small amount of road noise in
the A5 Cabriolet or TT Roadster, as the location of the microphone at the top of the windshield allows for noise
to be easily transmitted. None of the repairs below will eliminate this small amount of road noise.
If call quality issues are confirmed, proceed with the repair procedure below.
Remove the trim plate in order to inspect the microphone
1. Remove the roof module from the vehicle according to ElsaWeb>>Repair Manual>> Electrical
System>>Electrical Equipment>>96 Interior Lights, Switches>>Removal and Installation>>Roof Trim Lamps
and Switches.
2. Remove the decorative trim plate from the roof module in order to inspect the seal of the microphone:
For A6 and A7 vehicles:
• Remove the decorative trim from the base plate with
your fingers. If necessary, gently pry the trim with a
trim stick or bone tool, then finish removing it with
your fingers.
• There are a number of different clips holding the trim
plate to the base plate depending on the trim level of
the vehicle (Figure 1).

Figure 1. Clip location for A6/A7 high-line roof
module (left) and for mid-line roof module (right)

© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin
For TT and A5 Cabriolet vehicles:
• The decorative trim plate should only be pried from the base plate after the LED circuit boards are removed
from the LED jewels in order to prevent the LED jewels from breaking and causing a rattle after
reassembly.
• To remove the LED circuit boards, first pry the
top of the small circuit board away from the LED
jewel, in the direction indicated by arrow 1
(Figure 2). It will only need to be lifted 1-2mm.
Then, pull up on the circuit board in the direction
indicated by arrow 2 (Figure 2) to release the
circuit board from the LED jewel. There are
three different attachment points of the LED
circuit board and LED jewel (Figure 3).
• Repeat for the other side.
• Once the LED jewels are free from the circuit
boards, the decorative trim plate can be
Figure 2. Prying the LED circuit-board of the jewel.
detached from the base plate. Use your fingers
to pry the two pieces apart.
There are many clip points holding the two
pieces together. Sliding your finger slowly
around the perimeter is the most effective way to
separate the two parts without damaging them
(Figure 4).
Note:
The use of a bone tool or screw driver is not
recommended for this roof module assembly
because it can damage the soft touch paint on the
edge of the trim, which can be visible once the part
is reinstalled in the headliner.

Figure 3. LED jewel attachment points.

© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin

Figure 4. Prying the trim plate from the base plate.
Inspect and replace the microphone
1. Inspect the seal of the microphone for damage:
• There are two splits in the rubber seal. This is
normal as long as the two halves of the seal are
touching each other (Figure 5).

Figure 5. Undamaged seal

© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin
• If the two halves of the seal are loose and move
freely, the seal is damaged (Figure 6).

Figure 6. Examples of damaged seals
2. If none of the seals are damaged:
• Reinstall the microphones into the roof module. Ensure that the microphones are firmly seated. A loud
snap can be heard and felt when the microphone is fully seated. Reinstall the roof module and retest for the
complaint before proceeding with diagnosis. If the complaint cannot be reproduced, no additional action is
necessary.
If any of the seals are damaged:
• If the vehicle is a 2013+ A6/A7 built after VIN
DN005481, contact TAC prior to proceeding with
repairs for special instructions. When calling, please
provide repair order number, as well as part numbers
for microphones and interior light assembly.
• If the vehicle does not fall into the above range,
replace the microphone set by installing the
replacement microphone while the decorative trim is
removed from the base plate. Take care when doing
so to prevent damaging the new microphone’s seal by
slowly installing it perpendicular to the base plate
(Figure 7). Do not install the microphone at an angle,
as this may pinch the seal (Figures 8 and 9)

Figure 7. Proper installation.

Figure 8. Incorrect installation at an angle,
showing a pinched seal on the left.

© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin

Figure 9. Damage caused by a pinched seal.
• Carefully inspect the new microphone seal after it has been snapped into place.
3. If the vehicle is a TT or A5 Cabriolet:
• Visually inspect the round felt material on the
underside of the decorative trim (Figure 10). The
felt material pushes against the microphone’s
rubber seal and forms a barrier. The decorative
trim should be replaced (see ETKA) if the material
is bunched up or not centered perfectly, as it can
potentially affect the call quality.

Figure 10. Felt on backside of decorative trim.

© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin
• Before installing the new microphone, partially pull
out the foam that is inserted in the microphone to
allow for a better seal against the felt material
(Figures 11 and 12).

Figure 11. After modification, the foam should be
partially pulled out of the microphone.

Figure 12. Foam is partially pulled out of the
microphone.

© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin
Complete the repair
1. After the repair, road test the vehicle at a minimum speed of 45 mph with the top up (if applicable) and all
windows closed.
2. During the road test, verify the call quality issue by making a Bluetooth call to the same person at the
workshop that was called before the repair in order to verify call quality improvement.
3. If the call quality is still poor, call the Technical Assistance Center (TAC).
4. If the seals and microphones are installed properly, continue with diagnosis. Refer to TSB 2026895, 91
Microphone testing tips and TSB 2026888, 91 Bluetooth Phone: Poor call quality.

Warranty
Claim Type:

Use applicable claim type. If vehicle is outside any warranty, this Technical Service Bulletin
is informational only.

Service Number:

9157

Damage Code:

0010

Labor Operations:

Remove and install interior light

9620 1900

See Elsa

Remove and install telephone microphones

9157 1950

10 TU

Extended Road Test before and after repair

9157 9999

A-Time (Not to
exceed 40 TU)

GFF

No allowance

0 TU

Road test prior to service procedure

0121 0002

10 TU

Road test after service procedure

0121 0004

10 TU

Diagnostic Time:

Technical diagnosis at dealer’s discretion
(Refer to Section 2.2.1.2 and Audi Warranty Online for DADP allowance details)
Claim Comment:

As per TSB # 2027718/6

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.

© 2014 Audi of America, Inc.

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All rights reserved. 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.

Technical Service Bulletin
Required Parts and Tools
Part Number

Part Description

Quantity

See ETKA

Microphone

As needed

Additional Information
The following Technical Service Bulletin(s) may be necessary to complete this procedure:
•

TSB 2026895, 91 Microphone testing tips

•

TSB 2026888, 91 Bluetooth Phone: Poor call quality

All parts and service references provided in this TSB (2027718) are subject to change and/or removal. Always
check with your Parts Department and service manuals for the latest information.

© 2014 Audi of America, Inc.

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All rights reserved. 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.