No. 141-21-1

Service
Technical Information
141/21 ENU
AMB9
4
AMB9 – Reworking Brake Booster (Recall Campaign)
Vehicle Type:
911 Carrera (992) / 911 Carrera S (992) / 911 Carrera 4 (992) / 911 Carrera 4S (992) / 911
Targa 4 (992) / 911 Targa 4S (992)
Model Year:
As of 2020 up to 2021
Concerns:
Brake booster
Information:
On the affected vehicles, the screw of the brake booster's pressure input rod may not have
been connected according to specifications.
As a result, the pressure input rod may become loose from the brake booster over the vehicle's service
life. If the pressure input rod is loose, the vehicle cannot be braked using the brake pedal. The emergency
brake function via the electric parking brake is still available however without restrictions.
Action required: Rework the brake booster.
Affected
Vehicles:
Only vehicles assigned to the campaign (see also PCSS Vehicle Information).
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Oct 6, 2021
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Service
Technical Information
ENU 141/21
AMB9
Installation
Position:
Installation position of brake booster
1
– Brake booster (reworking)
Required tools
Tools:
•
•
•
•
•
Marker pen
Open-ended wrench a/f 7
Open-ended wrench a/f 16
Torque wrench, 6-50 Nm (4.5-37 ftlb.), e.g. VAG 1331A Torque wrench, 6-50 Nm (4.5-37 ftlb.)
Open-ended wrench attachment, for torque wrench a/f 16 (This tool will only be auto-shipped to
affected dealers by this campaign)
Preparatory work
Work Procedure: 1
2
Set driver seat to rearmost position.
Place steering wheel in upper position.
Reworking brake booster
Work
Procedure:
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Information
Do not pull on or put pressure on the brake pedal while working on the brake booster pressure input rod.
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Service
Technical Information
1
141/21 ENU
AMB9
4
Carefully press the dust glove on the pressure input
rod  Installation location of dust glove on pressure
input rod -1- back by approx. 1 cm/ 0.39 in with your
hand  Pressure input rod dust glove -Arrow-.
Installation location of dust glove
on pressure input rod
Pressure input rod dust glove
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Service
Technical Information
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AMB9
2
Carefully pull on screw connection for the pressure
input rod using open-ended wrench a/f 7  Screw
connection for pressure input rod -1- and torque
wrench using open-ended wrench attachment a/f
16  Screw connection for pressure input rod -2-.
torque 10 Nm (7.5 ftlb.)
Screw connection for pressure input rod
3
Mark both sides of the screw connection with a
continuous line  Marking on screw connection -1-.
Marking on screw connection
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Service
Technical Information
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141/21 ENU
AMB9
4
Turn the pressure input rod using an open-ended
wrench (a/f 16)  Pressure input rod -1- 45
degrees (counterclockwise)  Pressure input rod -in
direction of arrow-.
Pressure input rod
5
Check that the marking is then still at the same
position.
5.1
If the marking is still at the same position 
Position of marking -1-, continue with Step 6.
5.2
If the marking is at a different position 
Position of marking -2-, repeat the procedure
once, starting from Step 2.
Information
If the screw connection of the pressure input
rod can still be turned, replace the brake
booster in consultation with Technical
Support.  Workshop Manual '477019
Removing and installing brake booster'
Position of marking
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Oct 6, 2021
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Service
Technical Information
ENU 141/21
AMB9
6
Carefully pull the dust glove on the pressure input
rod back to  Pressure input rod dust glove -1- its
original position with your hand  Pressure input rod
dust glove -2-.
Pressure input rod dust glove
Concluding work
Work Procedure: 1
Return steering wheel to its original position.
2
Return driver seat to its original position.
3
Enter the campaign in the Warranty and Maintenance booklet.
Warranty processing
Scope 1:
Not valid for this vehicle type
Scope 2:
•
Valid for 911 (992)
Working Time:
Labor time: 49 TU
Reworking brake booster
Includes:
 Damage Code AMB9 099 000 1
Important Notice: Technical Bulletins issued by Porsche Cars North America, Inc. are intended only for use by professional automotive technicians who have attended Porsche service training
courses. They are written to inform those technicians of conditions that may occur on some Porsche vehicles, or to provide information that could assist in the proper servicing of a vehicle. Porsche special
tools may be necessary in order to perform certain operations identified in these bulletins. Use of tools and procedures other than those Porsche recommends in these bulletins may be detrimental to the
safe operation of your vehicle, and may endanger the people working on it. Properly trained Porsche technicians have the equipment, tools, safety instructions, and know-how to do the job properly and
safely. Part numbers listed in these bulletins are for reference only. The work procedures updated electronically in the Porsche PIWIS diagnostic and testing device take precedence and, in the event of a
discrepancy, the work procedures in the PIWIS Tester are the ones that must be followed.
© Porsche Cars North America, Inc.
Oct 6, 2021
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