NHTSA ID Number: 10244980
Manufacturer Communication Number: No. 137-23
TSB/Document Date: 2023-11-07
Summary
Symptom-based workshop manual for the brake system. Cracker or torn brake hose
on the left or right front axle.
Symptom-based workshop manual
Service
137/23 ENU
4726
4
Brake System Symptom - Cracked or Torn Brake Hose on the Left or Right Front Axle (SY
137/23)
Model Line:
Taycan (Y1A / Y1B / Y1C)
Model Year:
As of 2020
Concerns:
Symptom:
A cracked or torn brake hose is detected on the left or right front axle. Example of crack in brake hose
Example of crack in brake hose
Remedial
Action:
In the event of an incipient crack or crack on a brake hose on the front axle, both brake hoses on the
front axle must be replaced.
Required parts and materials
Parts Info:
Part No.
Designation
– Location of use
Number
Required parts for vehicles with front disc brake, standard (M-No. 1LS):
9J1611707C
Brake hose, front left
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
9J1611708C
Brake hose, front right
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
AfterSales
Oct 3, 2023
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4
Service
4726
ENU 137/23
Symptom-based workshop manual
or
9J0611707
Brake hose, front left
– Cross Turismo (M-No. K8X)
1 piece
9J0611708
Brake hose, front right
– Cross Turismo (M-No. K8X)
1 piece
Required parts for vehicles with front disc brake PSCB (M-No. 1LZ):
9J1611707B
Brake hose, front left
Up to model year 2021
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
9J1611708B
Brake hose, front right
Up to model year 2021
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
9J1611707F
Brake hose, front left
As of model year 2021
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
9J1611708F
Brake hose, front right
As of model year 2021
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
9J0611707A
Brake hose, front left
– Cross Turismo (M-No. K8X)
1 piece
9J0611708A
Brake hose, front right
– Cross Turismo (M-No. K8X)
1 piece
or
or
Oct 3, 2023
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AfterSales
Symptom-based workshop manual
Service
137/23 ENU
4726
4
Required parts for vehicles with front disc brake PCCB (M-No. 1LQ):
9J1611707B
Brake hose, front left
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
9J1611708B
Brake hose, front right
– Sport Turismo (M-No. K8D)
or
– Sports sedan (M-No. K8S)
1 piece
9J0611707B
Brake hose, front left
– Cross Turismo (M-No. K8X)
1 piece
9J0611708B
Brake hose, front right
– Cross Turismo (M-No. K8X)
1 piece
or
Materials:
Required materials (usually already available in the Porsche Center)
Part No.
Designation
Quantity
00004321086
Brake fluid (30-liter/ 7.9 gal container)
As required
Required tools
Tools:
•
•
•
Brake filling and bleeding equipment, e.g. VAS 6860 - brake filling and bleeding equipment
P90999 - PIWIS Tester 4
Battery charger with a current rating of at least 90 A, e.g. VAS 5908 - battery charger 90 A. For
further information about the battery chargers to be used, see the corresponding Workshop Manual.
Workshop Manual '270689 Charge 12-volt lithium-ion vehicle electrical system battery'
Preliminary work
Work Procedure: 1
2
Move the vehicle onto a lifting platform and raise it.
Workshop Manual '4X00IN Lift vehicle'
Remove front wheels.
Workshop Manual '440519 Remove and install wheel'
AfterSales
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Service
Symptom-based workshop manual
ENU 137/23
4726
Replacing front axle brake hoses
WARNING
Danger of injury and damage from brake fluid!
•
Poisonous if swallowed!
•
Irritation and damage to skin
•
Avoid contact with paint surfaces
Store brake fluid in suitable, labelled containers only
Wear protective gloves and goggles
In the event of contact (eyes or skin), wash immediately with water
In the event of contact with paint surfaces, wash off immediately with water - do not wipe off
Information
To gain better access for removing the brake hoses, turn the steering fully either to the left or right.
Information
The procedure for removing and installing is shown for one side as an example. The procedure for
removing and installing for the other side is almost identical.
Work
Procedure:
1
Loosen brake line on front axle.
1.1
Unscrew screw Front brake line on brake
calliper -1-. Remove loosened holder and fit it
on new brake line.
1.2
Unclip spring clamp Front brake line on
brake calliper -2- and disengage brake line
Front brake line on brake calliper -3- from
holder at the top.
1.3
Loosen and unscrew union nut for the brake
line Front brake line on brake calliper -4on the brake calliper Front brake line on
brake calliper -5-.
1.4
Oct 3, 2023
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Front brake line on brake calliper
Remove brake line Front brake line on brake calliper -3- and close line connections with
suitable stoppers while collecting leaking brake fluid using a suitable container.
AfterSales
Symptom-based workshop manual
2
4
137/23 ENU
4726
4
Remove front brake hose.
2.1
Loosen and unscrew union nut Front
brake hose on vehicle-side brake line -1- on
vehicle-side brake line Front brake hose
on vehicle-side brake line -3- to brake hose
Front brake hose on vehicle-side brake line
-2-.
2.2
Pull off brake hose Front brake hose on
vehicle-side brake line -2- and close line
connections with suitable stoppers while
collecting leaking brake fluid using a suitable
container.
2.3
3
Service
Front brake hose on vehicle-side brake line
Guide out brake hose Front brake hose on vehicle-side brake line -2-.
Install new brake hose.
3.1
Insert brake hose Front brake hose on
vehicle-side brake line -2- into the vehicle.
3.2
Push brake hose Front brake hose on
vehicle-side brake line -2- onto vehicle-side
brake line Front brake hose on vehicle-side
brake line -3-.
3.3
Screw on union nut Front brake hose
on vehicle-side brake line -1- securing the
vehicle-side brake line Front brake hose on
vehicle-side brake line -3-.
Front brake hose on vehicle-side brake line
Position front axle brake line.
4.1
Attach brake line Front brake line on brake
calliper -3- into the top holder and position on
the brake calliper Front brake line on brake
calliper -5-.
4.2
Screw on union nut Front brake line on
brake calliper -4-.
4.3
Position center holder for brake line and
tighten screw Front brake line on brake
calliper -1-.
4.4
Clip in spring clamp Front brake line on
brake calliper -2-.
AfterSales
Front brake line on brake calliper
Oct 3, 2023
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Service
ENU 137/23
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5
6
Symptom-based workshop manual
Fasten brake hose.
5.1
Tighten union nut securing vehicle-side brake line with tightening torque 14 Nm (10.3
ftlb.), do not twist brake line.
5.2
Tighten union nut securing brake calliper with tightening torque 14 Nm (10.3 ftlb.), do
not twist brake line.
5.3
Tighten screw securing center holder with tightening torque 8 Nm (5.9 ftlb.).
Repeat work procedure for front axle brake hose on the opposite side.
Follow-up actions
Work Procedure: 1
2
Bleed the brake system.
Workshop Manual '470107 Bleed the brake system'
Install front wheels.
Workshop Manual '440519 Remove and install wheel'
Labor position and PCSS encryption
Labor position:
APOS
Labor operation
47265690
Replacing front brake hose
47265691
Replacing front brake hose
I No.
Location (FES5)
47260
Front brake hose
Damage type (SA4)
1521
crack/incipient crack
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.
© 2023 Porsche Cars North America, Inc.
Oct 3, 2023
Page 6 of 6
AfterSales
- Mixes well with conventional fluids
- Low-moisture formula provides excellent vapor lock...
- Ideal for hydraulic and disc brakes
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TSB/Document ID: No. 137-23
Replacement Service Bulletin Number:
MFR Communication Date: 2023-10-03
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: SERVICE BRAKES
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
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