Service

Technical Information

116/23 ENU

WPK0

4

WPK0 - Re-Programming PSM Control Unit (Workshop Campaign)

Important:

CRITICAL WARNING -This campaign includes steps where control unit(s) in the vehicle will be
programmed with the PIWIS Tester. The vehicle voltage must be maintained between 13.5 volts and 14.5
volts during this programming. Failure to maintain this voltage could result in damaged control unit(s).
Damage caused by inadequate voltage during programming is not a warrantable defect. The technician
must verify the actual vehicle voltage in the PIWIS Tester before starting the campaign and also document
the actual voltage on the repair order.

Model Year:

As of 2020 up to 2024

Model Line:

Taycan (Y1A / Y1B / YBC)

Concerns:

Porsche Stability Management (PSM)

Cause:

An optimized software is available for the Porsche Stability Management (PSM) control unit.
This update optimizes the brake pedal feel on recuperative and hydraulic braking.

Action:

Check hydraulic unit and re-program PSM control unit using an updated data record.
Minimum requirement: Release 42.400.050

Affected
Vehicles:

Only vehicles assigned to the campaign (see also PCSS Vehicle Information).

Required materials
Material:

Required materials (usually already available in the Porsche Center or locally sourced):
Part No.

Designation

Quantity

00004321086

 Brake fluid, 30 liter/ 7.9 gal container

Quantity as required
(approx. 1 liter/ 33.8 fl oz
required per vehicle)

Required tools
Tool:

•
•
•

P90999 - P90999 - PIWIS Tester 4
Battery charger with a current rating of at least 90 A and a current and voltage-controlled
charge map for lithium starter batteries, e.g. VAS 5809 battery charger 90A
Torque wrench, 6 – 50 Nm (4.5 – 37 ftlb.), e.g. VAG 1331A Torque wrench, 6-50 Nm (4.5-37
ftlb.)

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Service

Technical Information

ENU 116/23

WPK0
•
•

Torque wrench, 150 – 800 Nm (111 – 592 ftlb.), e.g. VAG 1601 Torque wrench, 150 - 800 Nm
(111 - 592 ftlb.)
Suitable bleeding device for brake fluid, e.g., VAS 6860 - Brake filling and bleeding equipment

Checking hydraulic unit and re-program PSM control unit
Work Procedure: 1

Check hydraulic unit.
1.1

Connect and switch on the battery charger.

1.2

Connect the Tester to the vehicle and start it. Switch on ignition.

1.3

In the control unit Overview, select the control unit “Brake electronics (PSM incl. parking
brake)”.

1.4

Select the menu “Service and repairs”, then perform the function “Functional testing of
the hydraulic unit”, menu-guided.
Assessment

Action

( )

Bleed the brake system with the bleeding routine for
EBB.

Hydraulic unit function OK.

Continue with Step 1.6. Invoicing for Scope 1.
( )
Hydraulic unit function OK.
It is also suggested that
you perform a detailed
function test of the
hydraulic unit (expected
duration: 60 min.)
(✗)
Hydraulic unit function not
OK
(see also error message
below*)

Perform a detailed functional test of the hydraulic
unit. Then bleed the brake system with bleeding
routines EBB and PSM and re-program the PSM
control unit.
Continue with Step 1.5. Invoicing for Scope 2.

Replace the PSM control unit and hydraulic unit.
In this case, please send a PRMS ticket with
a screenshot of the error message via
the person responsible for the campaign to
PAG_Campaign_TI_SY_Support.
Only in the event of the aforementioned error message*
can you replace the PSM control unit and hydraulic unit
immediately after you have sent the ticket and without
waiting for the response. The invoice can be made via
a request for subsequent compensation to the original
campaign claim.
It is important to keep the removed parts, as they are
requested for analysis.

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Service

Technical Information

116/23 ENU

WPK0

4

Information
* Error message PSM control unit incl. hydraulic unit
In the event that the PSM control unit incl. hydraulic unit has a fault and must be replaced, the
following message is displayed in the PIWIS Tester:
“The brake system is faulty!
The function test of the hydraulic unit is completed. The brake system is defective.
Replace the complete PSM system.”

2

1.5

Only required after a detailed functional test of the hydraulic unit has been
completed successfully: Bleed the brake system with the bleeding routine Porsche
Stability Management (PSM).
 Workshop Manual '470107 Bleeding brake system'

1.6

Bleed the brake system with the bleeding routine for electric brake booster (EBB).
 Workshop Manual '470107 Bleeding brake system'

The basic procedure for control unit programming is described in the Workshop Manual 
Workshop Manual '9X00IN Basic Instructions and Procedure for Control Unit Programming Using the
PIWIS Tester'.
For specific information on control unit programming during this campaign, see the table
below.

Required PIWIS Tester software release:

42.400.050 (or higher)

Integration test procedure:

•
•

The integration test shows a green result
independently of the necessary campaign
The WPK0 campaign must still be carried
out

Type of control unit programming:

Control unit programming using the “Automatic
programming” function in the PSM control unit.

Programming sequence:

Read and follow the information and instructions
on the PIWIS Tester during the guided
programming sequence.
Do not interrupt programming and coding.
A backup documentation process for the
re-programmed software releases starts as soon
as programming and coding is complete.

Programming time (approx.):

12 minutes

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Technical Information

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WPK0

PSM control unit: 0190

Software release programmed during this
campaign:

•

Procedure in the event of error messages
appearing during the programming sequence:

 Workshop Manual '9X00IN Basic instructions

Procedure in the event of a termination in the
control unit programming:

Repeat control unit programming by restarting
programming.

3

Following control unit programming, the software
release can be read out from the relevant control
unit using the PIWIS Tester in the menu  “Incremented identifications”.

and procedure for control unit programming using
the PIWIS Tester'

Read out and delete all control unit fault memories.
3.1

In the control unit selection (“Overview menu”) press •F7“ to call up the Additional menu.

3.2

Select the function “Read all fault memories and erase if necessary” and press •F12“
(“Next”) to confirm.
Information
If control units are found to have faults that are not caused by control unit programming,
these must first be found and corrected. This work cannot be invoiced under the
workshop campaign number.

4

Press •F3“ to start the integration test in the control unit selection.
All affected control units should now be successfully re-programmed or checked in the control unit
overview and their status.
Information
If a deviation in the integration test is still indicated despite programming being carried out, this must
be repeated. If the deviation persists, contact Technical Support.

5

Exit the diagnostic application. Switch off ignition.

6

Switch off and disconnect the battery charger.

7

Enter the campaign in the Warranty and Maintenance logbook.

Warranty processing
Scope 1:

Not valid.

Scope 2:

Re-programming the PSM control unit – Bleeding the brake system with bleeding routine EBB

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Service

Technical Information

116/23 ENU

WPK0

4

Labor time:
Labor time: 151 TU

Re-programming PSM control unit
Includes:
Connecting and disconnecting battery charger
Connecting and disconnecting PIWIS Tester
Functional testing of the hydraulic unit
Removing and installing wheels
Bleeding brake system (EBB)
Reading out and deleting fault memories
Required materials:
00004321086

Brake fluid, 30 liter/ 7.9 gal container

0.04 piece
(approx. 1 liter/ 33.8 fl oz)

Only in the event that the 30 liter/ 7.9 gal container cannot be referenced, the 1 liter/ 33.8 fl oz
container can also be referenced and invoiced:
00004321082

Brake fluid, 1 liter/ 33.8 fl oz container

1 piece

 Damage Number WPK0 066 000 1
Scope 3:

Not valid.

Scope 4:

Re-programming the PSM control unit – Bleeding the brake system with bleeding routines EBB and PSM
Labor time:
Labor time: 171 TU

Re-programming PSM control unit
Includes:
Connecting and disconnecting battery charger
Connecting and disconnecting PIWIS Tester
Functional testing of the hydraulic unit
Removing and installing wheels
Bleeding brake system (EBB)
Reading out and deleting fault memories
Required materials:
00004321086

Brake fluid, 30 liter/ 7.9 gal container

0.04 piece
(approx. 1 liter/ 33.8 fl oz)

Only in the event that the 30 liter/ 7.9 gal container cannot be referenced, the 1 liter/ 33.8 fl oz
container can also be referenced and invoiced:
00004321082

Brake fluid, 1 liter/ 33.8 fl oz container

1 piece

 Damage Number WPK0 066 000 1

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WPK0

Technical Information

ENU 116/23

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.

© 2024 Porsche Cars North America, Inc.

Apr 8, 2024
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