A462124203418118

46 Brake noise analysis and handling
46 21 24 2034181/18 February 10, 2021. Supersedes Technical Service Bulletin Group 46 number 19-08 dated
March 18, 2019 for reasons listed below.
Model(s)
Year
VIN Range
Vehicle-Specific Equipment
All
2012 - 2022
All
Not Applicable
Condition
REVISION HISTORY
Revision
Date
Purpose
18
-
Revised header (Added model years)
17
03/18/2019
Revised Service (Updated procedure)
16
01/15/2019
Revised header (Added model years)
Revised Technical Background (Updated Note)
Revised Service (Updated procedure)
Customer states:
 They hear a brake noise from the front or rear brakes. The customer may describe these noises as a squeal,
squeak, grinding, groaning, thumping, or creaking.
Note:
DO NOT use this TSB if there is another brake noise TSB applicable to the VIN.
For additional information, refer to the Audi Brake systems brochure.
Technical Background
Brake noise can be attributed to many causes. The most common causes are:
1. Brake discs or brake pads are close to or below their wear limit.
2. New brake pads and/or discs have not been properly embedded after installation.
3. Aftermarket pads or discs are installed.
4. There is debris (such as small stones, grit, road salt, or sand) between the brake disc and brake pad.
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© 2021 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.
5. Discs are covered with rust. Rust can form
when the vehicle has not been driven for a
long period of time (Figure 1).
Figure 1. Disc covered with rust.
6. Discs are grooved (Figure 2).
Figure 2. Grooved disc.
7. There is chemical contamination on the
braking surface of the brake disc due to wheel
or tire cleaner being sprayed directly onto the
brake disc (Figure 3 and Figure 4).
Figure 3. Discoloration on the brake disc due to chemical
contamination from the cleaner that was sprayed directly
onto the disc.
Page 2 of 8
© 2021 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.
Figure 4. Small spots and discoloration due to chemical
contamination from the cleaner that was sprayed directly
onto the disc.
8. There are “pad marks” on the brake disc as a
result of brake pad material transferring to the
discs (Figure 5). Pad marks can occur when a
vehicle has been parked for long periods of
time in a wet or snowy environment.
Figure 5. Brake pad material has transferred to the discs.
Note:
For specific pulsation concerns, refer to TSB 2022584: 46 Brake pulsation diagnostic guidelines.
For specific frequency analysis, refer to TSB 2051095: 46 Audi frequency analysis.
Page 3 of 8
© 2021 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.
Production Solution
Not applicable.
Service
Proceed as follows:
1. Check the overall condition of the brakes to determine if the brake noise is caused by one of the causes
listed in the Technical Background section of this bulletin. If the noise is not a result of one of these causes,
proceed with the following steps 2-4.
2. Determine the location of the brake noise (e.g., left front, front axle, rear axle, etc.):
 Knowing the location of the noise on the vehicle is critical to properly addressing the concern.
 It may be necessary to have an assistant listening from inside or outside of the vehicle to accurately
determine the location.
3. Obtain a sound or video recording and fill out the questionnaire:
 The sound recording should be from a cell phone using the Audi analysis app (TSB 2051095: 46 Audi
frequency analysis) and the noise should be clearly identified.
 Recordings submitted by customers are also acceptable.
 In order to minimize file size, only sound recordings are necessary. Videos should only be sent if it is
critical for understanding the conditions under which the noise occurs.
 Fill out as much information as possible in the questionnaire. Some fields are mandatory.
4. Clean the brake pads and discs:
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© 2021 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.
A) With careful consideration of the traffic
situation, perform up to 5 ABS stops from speeds
above 50 mph. Between each ABS stop, allow the
brake components to cool by driving the vehicle
for more than one minute at speeds greater than
50 mph.
B) Let the vehicle sit for two hours to cool down.
C) Test drive again.
If the noise was not eliminated after completing
steps A and B, open a Technical Assistance
Center (TAC) ticket and include the following
information with the TAC ticket:
 Completed Brakes Acoustic Questionnaire.
 Sound or video recording (sound recording
preferred from Audi frequency app, see TSB
2051095: Audi frequency analysis).
 Frequency analysis (screenshot preferred
showing peak frequency, see figure 6).
Figure 6. Example of a frequency analysis screenshot.
 Photos of the affected brake discs and pads
that clearly show the condition of the braking
surface (see Figures 7 through 11).
Page 5 of 8
© 2021 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.
Figure 7. Example of the whole disc.
Figure 8. Example of brake system equipped guide pins
(showing all 4 guide pins).
Figure 9 and 10. Example of Inner and outer with an adhesive pad.
Figure 11. Example of pads without adhesive (mark position for reinstallation if not replaced).
5. Known brake noise frequency and repair suggestions:
Note:
The information below is only a reference for vehicles with a similar brake system, always review the specific
VIN for applicable TSBs. Review ELSA Repair Manual for specific brake system repair information.
Brake system ATE-TEVES with PR codes: 1LF/1LG/1LL/1ZK/1LJ/1LP:
Page 6 of 8
© 2021 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.
A) 1.6 KHz from front brakes. Inspect front pads.
B) 3.2 KHz/11 KHz from front brakes. Inspect front discs and pads.
Brake system TRW with PR codes : 1LA/1LB/1LD/1LT/1ZT/1LJ:
A) 1.6 KHz to 1.7 KHz from front brakes. Inspect front discs.
B) 3.2 KHz from front brakes. Inspect and if needed, suggest to clean and lube the guide pins in the caliper
carrier using anti-seize paste G052560A2.
C) 7.8 KHz from front brakes. Inspect front pads.
Warranty
Claim Type:
 110 up to 48 Months/50,000 Miles.
 If the vehicle is outside any warranty, this Technical Service Bulletin is informational
only.
Service Number:
4617
Damage Code:
0020
Labor Operations:
Clean brake pads and discs
4617 8099
70 TU
GFF
No allowance
0 TU
Road test prior to the service procedure
No allowance
0 TU
Road test after the service procedure
No allowance
0 TU
Includes: Road tests, submission of an audio file,
and questionnaire
Diagnostic Time:
Claim Comment:
As per TSB #2034181/18
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
The following Technical Service Bulletin(s) may be necessary to complete this procedure:
 TSB 2022584, 46 Brake pulsation diagnostic guidelines.
 TSB 2051095, 46 Audi frequency analysis.
Page 7 of 8
© 2021 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.
All parts and service references provided in this TSB (2034181) 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.
©2021 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.
Page 8 of 8
© 2021 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.