Service

Technical Information

2025

ENU

WSQ7

2

WSQ7 - Re-Programming High-Voltage Voltage Converter Control Unit (Workshop/OTA 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:

2025

Vehicle Type:

Taycan (Y1A/Y1B/Y1C)

Concerns:

High-voltage voltage converter control unit

Cause:

During DC rapid charging processes at public charging pedestals, charging current peaks that do not
comply with the standard can permanently lead to deactivation of the DC rapid charging option for
component protection.
As a result, the respective vehicle can then only be charged using alternating current (AC).

Action:

Re-program the high-voltage voltage converter control unit with the latest Porsche Tester software release
in each instance.
•

Minimum requirement: Version 43.700.040

Information
Scope definition
Scope 1: Over-the-Air (OTA) software update via PCM.
•

Please note that the OTA software updates should generally be installed by the driver (main user) via the
Porsche Communication Management (PCM), provided that the software package for the campaign has
been downloaded to the vehicle via OTA (Scope 1) and the update is subsequently displayed in the PCM
"Updates" menu.

Scope 2: Re-program the high-voltage charger (OBC) control unit using the Porsche Tester.
•

Affected
Vehicles:

For vehicles on which the preconditions for performing an OTA software update are not met at the
time of publication of the campaign (Non-Connect market/online software update in MyPorsche
deactivated/Privacy Mode/guest user), no OTA update is displayed in the vehicle (PCM). These vehicles
are therefore assigned to Scope 2 of this campaign and must be updated with the current Porsche
Tester software for the corresponding control unit.

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

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Feb 12, 2026
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Service
WSQ7

ENU

Technical Information

2025

Required tools
Tools:

•
•

P90999 - P90999 - Porsche Tester 4 with installed software release 43.700.040 (or higher).
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 5908 battery charger 90 A

Re-program the high-voltage voltage converter control unit.
Work Procedure: 1

Re-program the “High-voltage voltage converter” control unit.
The basic work procedure for control unit programming is described in the Workshop Manual. ⇒
Workshop Manual 'Basic instructions and procedure for control unit programming'
Specific information on control unit programming during this campaign:
Required Porsche Tester software release:

43.700.040 (or higher)

Type of control unit programming:

Control unit programming using the ‘Automatic
programming’ function of the high-voltage
voltage converter control unit.

Programming sequence:

Read and follow the information and instructions
on the Porsche 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 once
programming and coding is complete.

Programming time (approx.):

6 minutes

Software release programmed during this
campaign:

•

High-voltage voltage converter control unit
charger: 1407

Following control unit programming, the software
release can be read out from the respective control
unit using the Porsche Tester in the menu ⇒
‘Extended identifications’.

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Procedure in the event of error messages
appearing during the 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 abnormal termination
of control unit programming:

Repeat control unit programming by restarting
programming.

Read out and delete all control unit fault memories.

AfterSales

Service

Technical Information

2025

WSQ7

ENU

2

2.1

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

2.2

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

3

Press •F3“ to start the integration test in the control unit selection.
There must be no composite damage! Optional control unit updates can be ignored.
Information
If a deviation in the integration test is still indicated despite the programming carried out, this must be
repeated. If the deviation persists, contact Technical Support.

4

Enter the campaign in the warranty and maintenance logbook.

Warranty processing
Scope 1:

Over-the-Air (OTA) software update via PCM.
•

Scope 2:

No invoicing possible

Re-program the high-voltage voltage converter using the Porsche Tester control unit.
•

Vehicles without OTA activation
Labor time:
Re-program the high-voltage voltage converter control unit.
Includes:
Connect and disconnect the battery charger
Connecting and disconnecting Porsche Tester
Read out and delete the fault memory

Labor time: 44 TU

Þ Damage number WSQ7 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.

© 2026 Porsche Cars North America, Inc.

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