Service

Technical Information

173/23 ENU WPD8

2

WPD8 – Re-Programming High-Voltage Battery Control Unit (BMC) (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 2017 up to 2024

Change
Overview:

Version

Date

Change

0

04/09/2025

•

Original publication

1

05/29/2025

•

Update of PIWIS Tester
release version
Addition of Information
regarding the SOC (State
of Charge)

•

Model Line:

Cayenne (9YA / 9YB), Panamera (971)

Concerns:

High-voltage battery control unit (BMC)

Cause:

Due to a software error in the high-voltage battery control unit (BMC), the calculation of the calibration
test number (CVN) cannot be carried out in full on the affected vehicles.
This may lead to incomplete output of the on-board diagnostics in the event of a fault in the high-voltage
battery (BMC) control unit. As a result, country-specific regulations are not fulfilled.

Action:

Re-program the high-voltage battery control unit (BMC), and depending on the vehicle condition individual
cell modules, with the latest PIWIS Tester software release.
Minimum requirement: Release 43.400.030

Affected
Vehicles:

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

Required tools
Tools:

•
•

P90999 - PIWIS Tester 4
Battery charger with a current rating of at least 90 A, e.g. VAS5908 battery charger 90A

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May 29, 2025
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Service

Technical Information

ENU 173/23

WPD8

Re-program high-voltage battery control unit (BMC)
Work Procedure: 1

The basic procedure for programming a control unit is described in the Workshop Manual ⇒ Workshop
Manual '9X00IN Basic instructions and procedure for control unit programming using the PIWIS Tester
– section on "Programming"'.
Information
Please note, that the SOC (State of Charge) of the battery must not be below 40% before starting the
re- programming.
For specific information on control unit programming during this campaign, see the table below.

Required PIWIS Tester software release:

43.400.030 (or higher)

Type of control unit programming:

Control unit programming using the "Automatic
programming" function of the gateway control unit:
"High-voltage battery" control unit – "Coding /
Programming" menu – "Automatic programming"
function.

Programming sequence:

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

Programming time (approx.):

50 minutes

Software release programmed during this
campaign for vehicles depending on vehicle
condition:

Panamera (971)
•
•

High-voltage battery control unit (37 Ah) :
0293
High-voltage battery control unit (48 Ah) :
0373 or 0371

Cayenne (9YA / 9YB)
•
•

May 29, 2025
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AfterSales

High-voltage battery control unit (37 Ah) :
0293
High-voltage battery control unit (48 Ah) :
0373 or 0371

Service

Technical Information

173/23 ENU WPD8

2

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".
Procedure if error messages appear during
programming sequence:

⇒ Workshop Manual '9X00IN Basic instructions and
procedure for control unit programming using the
PIWIS Tester - section on "Troubleshooting"'.

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

Repeat control unit programming by restarting
programming.

2

Read out all fault memories, process and delete existing faults if necessary.
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.

3

Enter the campaign in the Warranty and Maintenance Logbook.
Continue to warranty processing ⇒ Technical Information '9X00IN Warranty processing'

Warranty processing
Scope 1:

Re-program high-voltage battery control unit (BMC)
Labor time:
Re-program high-voltage battery control unit (BMC)
Includes:
Connect and disconnect battery charger
Connect and disconnect PIWIS Tester
Read out and delete fault memory

Labor time: 70 TU

Þ Damage number WPD8 066 000 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.

© 2025 Porsche Cars North America, Inc.

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