NHTSA ID Number: 11013704
Manufacturer Communication Number: Circular 27BQ_REV10
TSB/Document Date: 2025-02-05
Summary
Under this service action, Audi dealers will replace the starter-alternator in affected vehicles at no cost to owners. A defective starter-alternator may inhibit start/stop functionality which could increase CO2 and other emissions while the vehicle is stopped. Emissions still remain within certification standards. Updated affected vehicle chart, owner notification letters, parts and claiming sections to reflect the addition of the final wave of vehicles. Updated note in Section C work instructions.
Emissions Service Action
Code: 27BQ
Subject
Document History
Affected Vehicles
Starter - Alternator
Date
Summary
01/07/2025
Updated note in Section C work instructions.
12/17/2024
Updated criteria in parts section.
12/06/2024
Updated affected vehicle chart, owner notification letters, parts and
claiming sections to reflect the addition of the final wave of vehicles.
Updated work instructions (battery charger must be connected
before checking starter/generator software version).
11/15/2024
Updated affected vehicle chart & owner notification letters to reflect
the addition of the next wave of vehicles.
10/24/2024
Updated parts table in parts section.
10/10/2024
Updated affected vehicle chart & owner notification letters to reflect
the addition of 2022 model year.
08/19/2024
Updated affected vehicle chart & owner notification letters to reflect
the addition of 2021 model year.
Parts and claiming instructions updated.
06/26/2024
Updated parts sections, claiming and work instructions.
06/11/2024
Updated coolant claiming quantity.
05/03/2024
Updated claiming instructions.
04/30/2024
Original publication.
Country
Beginning
Model
Year
Ending
Model
Year
Vehicle
USA
2020
2024
A6 ALLROAD
USA
2019
2024
A6 SEDAN
USA
2019
2024
A7
USA
2019
2024
A8
USA
2020
2024
Q7
USA
2019
2024
Q8
USA
2021
2024
RS6 AVANT
USA
2021
2024
RS7
USA
2020
2024
RSQ8
USA
2020
2024
S6 SEDAN
USA
2020
2024
S7
USA
2020
2024
S8
CAN
2020
2024
A6 ALLROAD
CAN
2019
2024
A6 SEDAN
CAN
2019
2024
A7
Vehicle
Count
The 27BQ
repair will
be launched
in multiple
waves.
The 27BQ
repair will
be launched
The repair information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These
procedures are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To
determine whether this information applies, contact an authorized Audi
dealer. 2025 Audi of America, Inc. and Audi Canada. All Rights Reserved.
27BQ Page 1 of 28
About this Emissions
Service Action
Code Visibility and
Owner Notification
CAN
2019
2024
A8
CAN
2020
2024
Q7
CAN
2019
2024
Q8
CAN
2021
2024
RS6 AVANT
CAN
2021
2024
RS7
CAN
2020
2024
RSQ8
CAN
2020
2024
S6 SEDAN
CAN
2020
2024
S7
CAN
2020
2024
S8
in multiple
waves.
Under this service action, Audi dealers will replace the starter-alternator in affected vehicles at
no cost to owners. A defective starter-alternator may inhibit start/stop functionality which could
increase CO2 and other emissions while the vehicle is stopped. Emissions still remain within
certification standards.
WAVE
CRITERIA
VISIBILITY/LAUNCH
DATE
CUSTOMER MAILING
DATE
1
C8, A8, 4M, SC, S8, RQ
April 30, 2024
May 2024
2
21, 22, 23, 24, 25, 26, 27
August 19, 2024
August 2024
3
31, 32, 33, 34, 35, 36, 37
October 10, 2024
October 2024
4
41, 42, 43, 44, 45, 46, 47
November 15, 2024
November 2024
5
51, 52, 53, 54, 55, 56, 57
December 06, 2024
December 2024
Emissions Campaigns
Requirements
(CALIFORNIA ONLY)
The California Air Resources Board and the Department of Motor Vehicles (DMV) require
emissions-related campaigns to be completed prior to vehicle registration renewal. When
campaign work is done you must provide the owner with a signed “Vehicle Emission Recall –
Proof of Correction” certificate (RC EMISCAVWAU). Order certificates online via the
Compliance Label Ordering portal at www.accessaudi.com.
Additional Information
Please alert everyone in your dealership about this action, including Sales, Service, Parts
and Accounting personnel. Contact Warranty if you have any questions.
Dealers must ensure that every affected inventory vehicle has this campaign completed before
delivery to consumers.
The information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These procedures
are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To determine whether
this information applies, contact an authorized Audi dealer. 2025 Audi Group of America, Inc. and Audi Canada. All Rights Reserved.
27BQ Page 2 of 28
Parts Information
Criteria
Quantity
Part Number
P.O.C. Part Description
SC, 24, 34, 44, 54
1
4N0-903-028-S
C8, A8, 4M, S8
21, 22, 23, 25
31, 32, 33, 35
41, 42, 43, 45
51, 52, 53, 55
1
4N1-903-028
RQ, RS
26, 27
36, 37
46, 47
56, 57
1
4N1-903-028-B
ALL
1
N -900-970-01
ALL
2
N -910-718-01
BOLT (if necessary)
C8, A8, 4M, SC
21, 22, 23, 24
31, 32, 33, 34
41, 42, 43, 44
51, 52, 53, 54
1
06M-121-488-A
GASKET
C8, 21, 31, 41, 51
1
06M-133-237-A
GASKET
4M, 23, 33, 43, 53
1
4M0-145-117
SEAL RING
RS, 26, 36, 46, 56
1
N -910-191-01
SEAL RING
S8, RS, RQ
25, 26, 27
35, 36, 37
45, 46, 47
55, 56, 57
4
N -910-968-01
S8, RS, RQ
25, 26, 27
35, 36, 37
45, 46, 47
55, 56, 57
1
WHT-008-729-A
SEAL RING
G -12E-100-1G CON
G12 EVO Coolant - Concentrate
(US Dealers)
G -12E-100-2G CON
G12 EVO Coolant - Concentrate
(Canadian Dealers)
G -12E-050-1G-RTU
G12 EVO Coolant - 50/50 Pre-mix
(US Dealers)
G -12E-050-2G-RTU
G12 EVO Coolant - 50/50 Pre-mix
(Canadian Dealers)
As needed
ALL
Ordering Method
Reference POC
comments
individually by part
number, or in the
POC Campaign
List
-OR-
As needed
NOTE: Approximately 3 liters of coolant should be needed for the repair.
The information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These procedures
are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To determine whether
this information applies, contact an authorized Audi dealer. 2025 Audi Group of America, Inc. and Audi Canada. All Rights Reserved.
27BQ Page 3 of 28
Initial Allocation:
NO
There will be no parts allocation.
NOTE
Your dealer’s Estimated Remaining Repairs by campaign can be found in Parts on Command.
Click on “View Campaign List” and review the Estimated Remaining Repairs column.
NOTE
Campaign parts should always be ordered as per the parts information in this circular. The ordering system will
supersede the part, if applicable.
The information in this document is intended for use only by skilled technicians who have the proper tools, equipment and training to correctly and safely maintain your vehicle. These procedures
are not intended to be attempted by “do-it-yourselfers,” and you should not assume this document applies to your vehicle, or that your vehicle has the condition described. To determine whether
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TSB/Document ID: Circular 27BQ_REV10
Replacement Service Bulletin Number:
MFR Communication Date: 2025-01-07
MFR Internal Campaign ID/Software Version: 27BQ
Communication Type: Service Campaign
NHTSA Components: UNKNOWN OR OTHER
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
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