No. 126-20

Service
Technical Information
126/20 ENU
2470
2
Complaint: Error Message “Engine Control System Fault” When Brake Pedal is Pressed
Slightly - Vehicle Can Still be Moved Normally (126/20)
Vehicle Type:
Cayenne E-Hybrid (9YA/9YB)
Model Year:
As of 2019 up to 2023
Equipment:
Emissions concept ULEV70
Emissions concept ULEV125
Concerns:
DME control unit
Information:
The error message “Engine control system fault” appears in the instrument cluster and the
fault memory entry “P057200 - Brake light switch – short circuit to ground” is stored in the fault
memory of the DME control unit.
Cause:
When the brake pedal is pressed slightly, disparate braking information may be supplied, which will result
in an error message. The distance sensor in the brake booster detects that the brake is pressed, while
the brake light switch indicates that the brake is not pressed.
Action required: In the event of a customer complaint and if the fault memory entry “P057200 - Brake light switch – short
circuit to ground” is stored, re-program the ‘engine electronics (DME)’ control unit.
Information
The total time required for control unit programming is approx. 12 minutes.
Required tools
Tool:
•
•
9900 - PIWIS Tester 3/ 4 with PIWIS Tester test software version 41.600.020 (or higher) installed
Battery charger with a current rating of at least 90 A, e.g. VAS 5908 battery charger 90A.
Preparatory work
NOTICE
Fault entry in the fault memory and control unit programming aborted due to low voltage.
•
Increased current draw during diagnosis or control unit programming can cause a drop in voltage, which
can result in one or more fault entries and the abnormal termination of the diagnostic process.

Before starting control unit programming, connect a suitable battery charger with a current rating of at
least 90 A to the vehicle.
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Technical Information
ENU 126/20
2470
NOTICE
Control unit programming will be aborted if the WLAN connection is unstable.
•
An unstable WiFi connection can interrupt communication between the PIWIS Tester and the vehicle
communication module (VCI). As a result, control unit programming may be aborted.

During control unit programming, always connect the PIWIS Tester to the vehicle communication module
(VCI) via the USB cable.
NOTICE
Control unit programming will be aborted if the driver's key is not recognized
•
If the driver's key is not recognized in the vehicle, control unit programming cannot be started or will be
interrupted.

Position the driver's key in the rear area of the left cupholder in the center console between the holding
struts (emergency start tray) in order to guarantee a permanent radio link between the vehicle and
driver's key.
NOTICE
Use of a PIWIS Tester test software version that is older than the prescribed version
•
Measure is ineffective

Always use the prescribed version or a higher version of the PIWIS Tester test software for control unit
programming and coding.
Work Procedure: 1
Position the driver key in the rear area of the left
cupholder in the centre console between the holding
struts (emergency start tray) in order to guarantee a
permanent radio link between the vehicle and driver
key Emergency start tray.
2
Carry out general preliminary work for control unit
programming as described in  Workshop Manual
'9X00IN Basic instructions and procedure for control
unit programming using the PIWIS Tester - section on
“Preliminary work”'.
Emergency start tray
Re-program DME control unit
Work Procedure: 1
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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”'.
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Technical Information
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Specific information on control unit programming in the context of this Technical Information:
Required PIWIS Tester software version:
41.600.020 (or higher)
Type of control unit programming:
Control unit programming using the ‘Automatic
programming’ function for the DME control unit:
‘Engine electronics (DME)’ control unit –
‘Coding/programming’ menu – ‘Automatic
programming’ function.
Read and follow the information and instructions
on the PIWIS Tester during the guided programming
sequence.
During the programming sequence, the DME control
unit is re-programmed and then automaticallyrecoded.
Programming sequence:
Do not interrupt programming and coding.
Once the control units have been programmed and
coded, you will be prompted to switch the ignition off
and then back on again after a certain waiting time.
Backup documentation of the new software versions is
then performed.
The programming sequence takes (approx.):
12 minutes
Data record (software part number and
software version) programmed for the DME
control unit during programming:
See  Technical Information '9X00IN Overview of the
programmed software versions'.
Procedure in the event of abnormal termination of control unit programming:
• Switch ignition off and then on again.
• Read out and erase the fault memory  Workshop
Manual '9X00IN Basic instructions and procedure
for control unit programming using the PIWIS Tester “Rework” section'.
• Repeat control unit programming by restarting
programming.
Procedure in the event of other 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”'.
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Technical Information
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2470
Overview of the programmed software versions
Information
The software part number and software version of the programmed data record are based on the
specified PIWIS Tester test software version. Please note that these may have changed in a higher
version.
Exhaust
emission
standard
Model year
2019 (K)
2020 (L)
2021 (M)
2022 (N)
2023 (P)
-
-
x
x
x
-
x
-
-
-
ULEV70
ULEV12
5
Control
unit
Software part
no.
Software
version
DME
9Y0907
559AB
0006
DME
9Y0907
559R
0001
Concluding work
Work Procedure: 1
Carry out general reworking for control unit programming as described in  Workshop Manual
'9X00IN Basic instructions and work procedure for control unit programming using the PIWIS Tester “Reworking” section'.
Invoicing
Invoicing:
For documentation and warranty invoicing, enter the labor operations and PQIS coding specified below in
the warranty claim:
APOS
Labour operation
I No.
24702507
Re-programming DME control unit
PQIS coding:
Location (FES5)
24700
DME control unit
Damage type (SA4)
1134
Programming error
References:
 Workshop Manual '9X00IN Basic instructions and procedure for control unit programming using the
PIWIS Tester'
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Technical Information
126/20 ENU
2470
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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.
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