2023-2024 BMW Seat Initialization Loss SIB 52 02 24

Owners of certain 2023-2024 BMW models may experience issues with their driver's seat, including the BMW seat initialization loss, leading to various warning messages and loss of functionality. This problem is detailed in BMW Service Information Bulletin SIB 52 02 24, which supersedes the previous SI B52 02 24 dated July 2024.

Symptoms

Drivers may first notice Check Control messages (CCM) appearing at the end of a driving cycle. These messages indicate a problem with the seat's calibration or restraint system. If ignored, the seat may eventually stop functioning, and the airbag warning lamp could illuminate.

Common warning messages include:

• "CCM 434 Seat calibration required."
• "CCM 108 Driver restraint system."
• "CCM 97 Restraint system."
• "CCM 109 “Passenger restraint system”"

These messages signify that the seat initialization and memory functions have been lost or are repeatedly failing.

Fault Codes / DTCs

When these symptoms occur, several Diagnostic Trouble Codes (DTCs) may be stored in the vehicle's control modules. These codes help technicians pinpoint the exact nature of the fault.

Code	Description	Module
930D86	Function restraint system driver restricted.	ACSM6 Air Bag module
C95432	seat module Driver (seat memory), message status backrest locking standardization required.	ACSM6 Air Bag module
C95434	seat module Driver (seat memory), message status backrest locking standardization recommended.	ACSM6 Air Bag module
8029F5	initialization seat: limited seat adjustment due to missing calibration.	FAS_I20 Driver's Seat module
802A03	Functions seat adjustment FAS limited available.	FAS_I20 Driver's Seat module
802A05	ÜKB: Shut-off ÜKB because of missing calibration.	FAS_I20 Driver's Seat module

Diagnosis / Trigger Conditions

The BMW seat initialization loss typically occurs due to unfavorable software in the Basic Central Platform (BCP) control module. The BCP module can generate a Check Control Message (CCM) when the seat reaches approximately 2800 cycles, especially if the ACSM6 module also registers fault code C95434, recommending backrest locking standardization.

If the driver ignores this initial message, the seat may reach 3000 cycles. At this point, the ACSM6 module sets fault C95432, indicating that backrest locking standardization is required. Additionally, the airbag warning light may turn on because the seat length position is set to an invalid state, requiring a full seat standardization procedure.

Repair Procedure Summary

The repair for the BMW seat initialization loss involves updating the vehicle's software. Technicians will first determine the vehicle's current integration level (I-level) using applications like AIR or ISPA Next/AWP. If the current I-level is lower than the target integration level (e.g., G070-23-11-500 for G60/G70 models), the vehicle will be programmed using ISTA 4.44.2 or a higher version.

If the vehicle's I-level is already at or above the target, the customer can typically calibrate the seat themselves by following the instructions in the user manual to move the seat back and forth completely. The programming process through ISTA will automatically reprogram and code all control modules that do not have the latest software.

Required Tools or Parts

For the software programming procedure, a BMW-approved battery charger/power supply is essential to maintain stable voltage. The programming is performed using the ISTA diagnostic software, specifically version 4.44.2 or newer, which was released in November 2023.

Important Warnings

• Always connect a BMW-approved battery charger/power supply (as noted in SI B04 23 10) when performing programming to prevent voltage-related issues.

Owner Action

If you are experiencing any of the described Check Control messages or issues with your driver's seat, including BMW seat initialization loss, it is recommended to contact your authorized BMW dealer. They will be able to diagnose the specific fault codes and perform the necessary software update or guide you through the seat calibration process if your vehicle's software is already up to date. This repair is covered under the BMW New Vehicle Limited Warranty or BMW Certified Pre-Owned Program, if applicable.

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Source: NHTSA ID: 11006734