NHTSA ID Number: 10249236
Manufacturer Communication Number: Circular 91FN
TSB/Document Date: 2024-02-06
Summary
Affected vehicles will receive the latest software version via a software update. This software contains an optimized self-diagnosis function for the high-voltage battery
. In addition to the software update, the high-voltage battery cells may experience an increased self-discharge. The high-voltage battery will be evaluated, and any affected high-voltage cell modules will be replaced.
CONNECTION
1.00
1EA998103
SEP. FILM
1.00
1HV915754A
VALVE
1.00
D 316000A1
WAX UNDERCOAT
1.00
D 454300H2
SEALANT
CELL MOD*
Continued on next page
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. 2024 Audi of America, Inc. and Audi Canada. All Rights Reserved.
91FN Page 6 of 48
PARTS (continued)
Quantity
Quantity
Quantity
1.00/cell module
D G00018M3
Paste
Up to 40.00
or
Up to 2.00
G 12E100S1
or
G 12E050S0
COOLANT (concentrate)
or
COOLANT (pre-mix)
USA
ONLY
Up to 40.00
or
Up to 80.00
G 12E100S1
or
G 12E050S0
COOLANT (concentrate)
or
COOLANT (pre-mix)
CANADA
ONLY
4.00
N 10225202
BOLT, HEX. HD. (COMBI.)
(only needed if HV battery is being removed for
the first time)
24.00
N 90942804
BOLT, HEX. HD. WITH SHOULDER
4.00/cell module
N 91280901
Screw
4.00
N 91283201
22.00
WHT008738A
BOLT
82.00
WHT009218
The following can be added if the HV battery cover required replacement
PARTS
Quantity
Part Number
Description
1.00
1EA804841AC
HOUSING
8.00
1EA804973
HOLDER
1.00
1EA010505
WARN. SIGN
1.00
12E010006AA
STICKER
The following can be added as needed in the event of breakage during the repair.
PARTS
Vehicle Loaner
(if required)
Quantity
Part Number
Description
As required
WHT003491
NUT
As required
WHT009733
As required
N 0385494
Enter vehicle loaner claim as a separate (2nd) claim
Claim Type
7 MO
Service Number
91FN
Damage Code
0010
Parts Vendor Code
002
Outside Labor Operation
LOAN1600
(letter O, not number 0)
Enter dollar amount on
rental/loaner invoice
($50 max per day)
(2 day maximum)
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. 2024 Audi of America, Inc. and Audi Canada. All Rights Reserved.
91FN Page 7 of 48
Customer Letter Example (USA)
This notice applies to your vehicle: ,
Subject: Service Action 91FN - Software Update for High Voltage Battery Control Module - Version 3.2.1
Dear Audi Owner,
As part of Audi’s ongoing commitment to customer satisfaction, we are informing you of our decision to conduct a
service action on certain 2022-2023 model year Audi vehicles. Our records show that you are the owner of a vehicle
affected by this action.
About this Service Action: Affected vehicles will receive the latest software version via a software update. This
software contains an optimized self-diagnosis function for the high-voltage battery.
In addition to the software update, the high-voltage battery cells may experience an
increased self-discharge. The high-voltage battery will be evaluated, and any affected
high-voltage cell modules will be replaced.
What will we do?
Your authorized Audi dealer will perform a software update and evaluate your vehicle
to determine if any battery cell module(s) needs replacement. This work will take about
three (3) hours to complete and will be performed for you free of charge.
If the evaluation shows a battery cell module(s) needs replacement, the work to do the
replacement will take at least one day to complete once your dealer has the necessary
parts and equipment on hand, and will be performed for you free of charge. Please
keep in mind that your dealer will need additional time for the preparation of the work,
as well as to accommodate their daily workshop schedule.
What should you do?
In order to limit any possible inconvenience, please contact your authorized Audi dealer
as soon as possible to schedule this work. For your convenience, you can also visit
www.audiusa.com and click on the “Find a Dealer” link to locate a dealer near you and
schedule this service.
This service action will be available for you free of charge only until January 31, 2029.
If you wish to have this service performed after that date, your dealer’s normal costs
associated with this repair will apply.
Lease vehicles and
address changes
If you are the lessor and registered owner of the vehicle identified in this action, please
forward this letter immediately via first-class mail to the lessee within ten (10) days of
receipt. If you have changed your address or sold the vehicle, please fill out the
enclosed prepaid Owner Reply card and mail it to us so we can update our records.
Can we assist you
further?
If your authorized Audi dealer fails or is unable to complete this work free of charge
within a reasonable time, please contact Audi Customer Experience at 1-800-253-2834
or via our “Contact Us” page at www.audiusa.com.
Checking your vehicle for To check your vehicle’s eligibility for repair under this or any other recall/service
open Recalls and Service campaign, please visit the Recall/Service Campaign Lookup tool at
www.audiusa.com and enter your Vehicle Identification Number (VIN).
Campaigns
We apologize for any inconvenience this matter may cause; however we are taking this action to help ensure your
vehicle continues to meet and exceed your expectations.
Sincerely,
Audi Customer Protection
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. 2024 Audi of America, Inc. and Audi Canada. All Rights Reserved.
91FN Page 8 of 48
Customer Letter Example (Canada)
This notice applies to your vehicle: ,
Subject: Service Action 91FN - Software Update for High Voltage Battery Control Module - Version 3.2.1
Dear Audi Owner,
As part of Audi’s ongoing commitment to customer satisfaction, we are informing you of our decision to conduct a
service action on certain 2022-2023 model year Audi vehicles. Our records show that you are the owner of a vehicle
affected by this action.
About
Action:
this
Service Affected vehicles will receive the latest software version via a software update. This
software contains an optimized self-diagnosis function for the high-voltage battery.
In addition to the software update, the high-voltage battery cells may experience an
increased self-discharge. The high-voltage battery will be evaluated, and any affected
high-voltage cell modules will be replaced.
What will we do?
Your authorized Audi dealer will perform a software update and evaluate your vehicle
to determine if any battery cell module(s) needs replacement. This work will take about
three (3) hours to complete and will be performed for you free of charge.
If the evaluation shows a battery cell module(s) needs replacement, the work to do the
replacement will take at least one day to complete once your dealer has the necessary
parts and equipment on hand, and will be performed for you free of charge. Please
keep in mind that your dealer will need additional time for the preparation of the work,
as well as to accommodate their daily workshop schedule.
What should you do?
In order to limit any possible inconvenience, please contact your authorized Audi dealer
as soon as possible to schedule this work. Please keep in mind that your dealer may
need additional time for the preparation of the work, as well as to accommodate their
daily workshop schedule.
This service action will be available for you free of charge only until January 31, 2029.
If you wish to have this service performed after that date, your dealer’s normal costs
associated with this repair will apply.
Lease vehicles and
address changes
If you are the lessor and registered owner of the vehicle identified in this action, please
forward this letter immediately via first-class mail to the lessee within ten (10) days of
receipt. If you have changed your address or sold the vehicle, please fill out the
enclosed prepaid Owner Reply card and mail it to us so we can update our records.
Can we assist you
further?
If your authorized Audi dealer fails or is unable to complete this work free of charge
within a reasonable time, please contact Audi Customer Relations Monday through
Friday from 8AM to 8PM EST at 1-800-822-2834 or via our “Contact Audi Canada”
page at www.audi.ca.
We apologize for any inconvenience this matter may cause; however we are taking this action to help ensure your
vehicle continues to meet and exceed your expectations.
Sincerely,
Audi Customer Protection
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. 2024 Audi of America, Inc. and Audi Canada. All Rights Reserved.
91FN Page 9 of 48
Safety Precautions When Working ON the High-voltage System
(additional information is also available in the ELSA Repair Manual)
DANGER
Extremely dangerous due to high voltage.
•
The high-voltage system is under heavy voltage. Severe bodily injury or death by electrocution or electric
arcs is possible.
•
When working on the high-voltage system the high-voltage system must be de-energized.
•
When performing procedures that do not directly affect the high-voltage system, in some cases it is still
necessary to de-energize the high-voltage system.
•
Pay attention when the high-voltage system must be de-energized. Refer to the Repair Manual
•
Have a High-Voltage Technician or a High-Voltage Expert de-energize the high-voltage system.
The electric and magnetic fields are extremely dangerous.
•
There are electric and magnetic fields on the high-voltage system. Death or serious injury are possible due
to malfunction of active implants (for example cardiac pacemakers, insulin pumps).
•
Persons with active implants may not perform procedures on the high-voltage system.
WARNING
Risk of injury - motor may start unexpectedly
It is difficult to determine whether the drive system of an electric vehicle or hybrid vehicle is active. Moving parts can
trap or draw in parts of the body.
CAUTION
Risk of damage to high-voltage wiring
•
Incorrect handling may result in damage to the insulation of high-voltage wires or high-voltage connectors.
•
Do not support yourself on high-voltage cables or connectors.
•
Never prop tools against high-voltage wiring or high-voltage connectors.
•
Never bend or kink high-voltage wiring.
•
Observe the coding of the high-voltage connectors when joining them up.
Safety Precautions When Working NEAR the High-voltage System
(additional information is also available in the ELSA Repair Manual)
DANGER
Extremely dangerous due to high voltage.
•
The voltage levels in the high-voltage system constitute a safety hazard. Danger of severe or fatal injuries
from electric shock if high-voltage components or high-voltage wiring are damaged.
•
Carry out a visual check of high-voltage components and high-voltage wiring.
•
Never use cutting/forming tools or other sharp-edged implements.
•
Never perform work using welding, brazing, thermal bonding or hot air in the area of high-voltage
components and high-voltage cables.
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. 2024 Audi of America, Inc. and Audi Canada. All Rights Reserved.
91FN Page 10 of 48
DANGER
High voltage increases the risk of fatal injury
Electrocution can cause severe bodily or fatal injury.
•
For the following procedures suitable personal protective equipment must be worn.
•
For the following steps two correspondingly qualified technicians must be present for the supervision.
•
If necessary, a second technician can help the high-voltage expert outside of the hazardous area within
their qualification.
•
The personal protective equipment (PPE) must be dry and undamaged.
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. 2024 Audi of America, Inc. and Audi Canada. All Rights Reserved.
91FN Page 11 of 48
Repair Overview
IMPORTANT
If the vehicle being worked on also has the 91EV campaign assigned, the 91EV flash must be completed before
attempting the 91FN.
If the 91EV is performed before the 91FN, a bus sleep MUST be performed after the 91EV was completed and
before the 91FN is started.
•
Check HV battery cell modules via a test
plan.
•
Update vehicle software using a multi-step
software update process.
•
Replace HV battery cell module(s) based on
test plan results, if necessary.
NOTE
•
These repair instructions may differ from the labor operations and labor times listed in ELSA.
•
Damages resulting from improper repair or failure to follow these work instructions are the dealer’s
responsibility and are not eligible for reimbursement under this action.
•
This procedure must be read in its entirety prior to performing the repair.
•
Due to variations in vehicle equipment and options, the steps/illustrations in this work procedure may not
identically match all affected vehicles.
•
Diagnosis and repair of pre-existing conditions in the vehicle are not covered under this action.
•
When working during extreme temperatures, it is recommended that the vehicle be allowed to acclimate
inside the shop to avoid temperature-related component damage/breakage.
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. 2024 Audi of America, Inc. and Audi Canada. All Rights Reserved.
91FN Page 12 of 48
Required Tools (for software flash)
Battery Tester/Charger
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If the TSB PDF does not show, download or view it on the NHTSA Website.
Click on the (+) Plus Sign
Then Click on Associated Document(s)
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TSB/Document ID: Circular 91FN
Replacement Service Bulletin Number:
MFR Communication Date: 2024-01-19
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: BACK OVER PREVENTION:SOFTWARE
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
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