No. 2408

Bulletin #: 2408
Advanced Technical Information
Part ID: 2804
2
Ignition Lock Error B143C29
Vehicles Affected
Models
Model Year
Model Type
VIN Range
Vehicle-Specific Equipment
911
As of 2020 up to 2024
992
N/A
N/A
Cayenne
As of 2019 up to 2023
9YA, 9YB
N/A
N/A
Panamera
As of 2017 up to 2023
971
N/A
N/A
Revision History
Revision
Release Date
Changes
0
February 28, 2024
Original document, replaces ATI Group 2 2125.1, dated 01/07/2022.
Condition
The customer states a white warning message appears in the instrument cluster upon starting the engine. The 		
workshop either confirms the warning message in the cluster and/or finds the Rear-end electronics (BCM2) fault
entry “B143C29 – Ignition starter switch – signal implausible”.
Technical Background
The ignition switch is a four-signal redundant system to ensure proper operation even if one of the signals is corrupted. The signals are diagnosed by the BCM2 through each full cycle (vehicle off to engine running).
If the ignition switch is not fully engaged to start the engine, one of the four signals will not be switched (open line).
However, due to the design of the redundant system, the engine will still start. If the diagnostic for this signal continuously sees an open line, the fault will eventually be set in the BCM2.
To verify this issue, please take a VAL and check for BCM2 B143C29 fault entry freeze frame data and compare to
the bitcode below.
Freeze Frame data for “B143C29 – Ignition starter switch – signal implausible”:
20_Fault occurrence – measured values 10100000000000000000000000000
AfterSales
Feb 28, 2024
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Bulletin #: 2408
Advanced Technical Information
Part ID: 2804
2
Service Information
Please advise the customer to fully engage the ignition switch to start the engine each time to ensure the system
functions as designed and a real fault can be diagnosed. The image below shows a partial switch engagement,
which will lead to this fault after enough occurrences. Since this is a redundant system, the engine will start and
there will be no warning that it is being misused until the diagnostics eventually sets the fault after the threshold is 		
reached.
Figure 1
At the following link you will find a video recording of a vehicle subject to a complaint:
https://ppn.porsche.com/portal/docs/DOC-500167
Note:
The process to start the engine engine was already repeated 4 times, before the video was recorded.
Overall the engine has been started 5 times. The warning message is showing after the 6th attempt.
AfterSales
Feb 28, 2024
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Bulletin #: 2408
Advanced Technical Information
Part ID: 2804
2
Warranty
As there is no functional defect, the work steps as described in this ATI are excluded from Warranty and Goodwill.
Search Items
Ignition lock error, starter, ignition switch, rotor, dummy, key
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.
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Feb 28, 2024
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