Technical Service Bulletin
94 Moisture accumulation in headlamps
94 12 98 2028277/4 November 21, 2012. Supersedes Technical Service Bulletin Group 94 number 12-91 dated
October 24, 2012 for reasons listed below.
Model(s)

Year

VIN Range

Vehicle-Specific Equipment

Q7

2010 - 2014

All

Not Applicable

Condition
REVISION HISTORY
Revision

Date

Purpose

4

-

Revised Service
Revised Warranty
Revised Required Parts and Tools
Revised Header data (added model years)

3

10/24/12

Revised Required Parts and Tools
Revised Production Solution

2

3/1/12

Revised Service
Revised Required Parts and Tools

1

12/20/2011

Original publication

Page 1 of 7
© 2012 Audi of America, Inc.
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
Customer Complaint:
 Considerable moisture present in
headlamp.
 The moisture disappears only after
extended drives (greater than 10
minutes).
Workshop Findings:
 No external damage to headlamp
which could introduce moisture.

Figure 1. Moisture in headlamp.

Technical Background
Humid air settles on the inside of the glass, causing moisture to appear on the inside of the headlamp lens.
Because of the headlamp circulation system, outside air is allowed to flow through the headlamps. The open,
water-protected ventilation system (needed for pressure compensation) creates different “ climate zones”
inside the headlamp, where the lens is either warmed up by the light or cooled down by passing air.
When high air humidity and temperature differences exist between the inside of the headlamps and the outside,
condensation can form on the inside of the lens, especially in cold and wet weather. The moisture in the
headlamps can be compared with condensation on the windshield, which is cleared by the "defroster vent". This
moisture buildup can happen for example: after a car wash, after steam cleaning of the engine or the front end, or
after overnight temperature changes.
This condition is more easily visible with headlamps made from clear glass. The moisture is an optical condition
which does not affect the headlamp function (light performance) and does not lead to corrosion nor does it lead to
damage of the internal headlamp parts.
This condition is common to all exterior vehicle lights, and can occur on every headlamp, fog lamp, or rear lamp.

Production Solution
Optimized headlamp ventilation hose placed into production for all XENON headlamps.

Page 2 of 7
© 2012 Audi of America, Inc.
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
1. Remove the headlamps and dry the inside using compressed air or hot air blower.
2. If vehicle’ s build is prior to VIN #
*CD004736, replace the headlamp
ventilation hose for each headlamp
with the new part number to help
reduce any further humidity ingress
into the headlamps (see Part
information table below). Otherwise,
move to step 3.
The updated ventilation hose can be
recognized by the integrated filter
(Figure 2).

Figure 2. Updated ventilation hose with integrated filter.
3. Cut two sections of butyl cord
sealant, 8cm long each (Figure 3).

Figure 3. Butyl cord sealant, 10mm diameter.

Page 3 of 7
© 2012 Audi of America, Inc.
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
4. Each headlight ventilation guide
tube must be sealed to protect
against further moisture ingress
(Figure 4).

Figure 4. Headlamp ventilation guide tube.
5. Wrap butyl cord sealant around the
left and right ventilation tubes, taking
care not to block the air passage
tube (Figure 5).

Figure 5. Initial butyl cord shown on guide tube.

Page 4 of 7
© 2012 Audi of America, Inc.
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
6. Knead the butyl cord sealant in
place. The butyl sealant must be
excessive enough so that the
headlamp housing squeezes it and
creates a robust seal at the housing
(Figure 6).

Figure 6. Butyl cord kneaded in place.
7. Leave an uncovered section of the
air tube so that there is no chance
the sealant will clog the air passage
tube (Figure 7).

Figure 7. View of direction of headlamp engagement, with
appropriate butyl cord application.

Page 5 of 7
© 2012 Audi of America, Inc.
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
8. Reinstall headlamps. The headlamp housings will take more force than usual to install, as the butyl
must be compressed down and backwards.
Tip: When installing the headlamp, do not work back and forth during reinstallation, as this will
disrupt the butyl seal. If this occurs, remove the headlamp completely and knead the sealant back in
place to ensure a good seal.
If the headlamps were removed after butyl cord was already installed from a prior procedure,
remove old sealant and replace with new sealant.
9. Please inform the customer the new ventilation hoses and sealant are only to help reduce the
moisture condition, but will not eliminate this condition completely. Moisture in the headlamp lens is
normal and can occur even with the improved filtration.

Warranty
Claim Type:

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

Service Number:

9415

Damage Code:

0010

Labor Operations:

Remove and reinstall both headlamps

9415 2001

50 TU

Modify both headlamps and mounting

9415 5099

40 TU

GFF – Checking and clearing fault codes

No allowance

0 TU

Road test prior to service procedure

No allowance

0 TU

Road test after service procedure

No allowance

0 TU

Diagnostic Time:

included in existing labor operations

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

Page 6 of 7
© 2012 Audi of America, Inc.
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
Claim Comment:

As per TSB #2028277/4

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.

Required Parts and Tools
Part Number

Part Description

Quantity

4L0941717A

Left Headlamp Ventilation Hose

1 (if necessary)

4L0941718A

Right Headlamp Ventilation Hose

1 (if necessary)

AKD49701004R10

Butyl Cord Sealant

1

Additional Information
The following Technical Service Bulletin(s) will be necessary to complete this procedure:
 TSB 2012749, 94 Exterior lights, moisture accumulation
All parts and service references provided in this TSB are subject to change and/or removal. Always check with
your Parts Department and service manuals for the latest information.

Page 7 of 7
© 2012 Audi of America, Inc.
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.