2021 BMW X3 / X4 Active PDC Undesired Braking TSB

Symptoms

Owners of 2021 BMW X3 and X4 vehicles may notice their car applying the brakes autonomously. This specific issue occurs when the vehicle is reversing onto an inclined roadway or driveway. The BMW X3 X4 undesired braking symptom is directly linked to the Active Park Distance Control (PDC) option being active via the iDrive system.

Cause

The root cause of this unexpected braking behavior is a software anomaly within the ultrasonic sensors and the Park Distance Control (PDC) control unit. This software error leads to the system misinterpreting conditions when reversing on an incline, triggering the brakes unnecessarily.

Repair Procedure Summary

To correct the BMW X3 X4 undesired braking issue, technicians will perform a coding-only conversion. This involves modifying the vehicle order (VO) to add the specific code "PDCD". The procedure includes several key steps:

1. The technician will first attempt to duplicate the issue to confirm the symptom.
2. A diagnostic scan will be performed using ISTA 4.19.1 (released early September 2019) or a newer version.
3. Any related fault codes stored in the vehicle's system will be addressed through a complete test plan.
4. With the vehicle connected to ISTA 4.19.1x or higher, the technician will navigate to the conversions section.
5. They will select the option labeled "PDC ground detection when reversing".
6. Finally, a coding-only conversion will be executed to add "PDCD" to the vehicle's order. This update specifically addresses the software logic for PDC ground detection when reversing.

For additional information regarding the limitations of the PDC system, technicians are advised to refer to Technical Reference Information Bulletin TRI B66 11 18.

Important Warnings

When performing any programming or coding procedures on the vehicle, it is crucial to always connect a BMW-approved battery charger or power supply. This ensures stable voltage throughout the process and prevents potential issues. Refer to Service Information Bulletin SI B04 23 10 for detailed guidelines on connecting a battery charger/power supply.

Affected Components and Codes

This Service Information Bulletin (SIB 66 17 19) applies to BMW X3 (G01) Sports Activity Vehicles produced from August 1, 2017, to July 2021, and BMW X4 (G02) Sports Activity Coupes produced from April 1, 2018, to July 2021. The issue specifically affects vehicles equipped with option code 5DM (Parking Assistant) or 5DN (Parking Assistant Plus).

The defect code associated with this issue is 6620010200, which identifies a "Control unit, Park Distance Control (PDC) software error/internal equipment fault". The resolution involves a software update that adds the "PDCD" keyword to the vehicle order.

Warranty Information

This repair, including the vehicle test and the coding conversion to add "PDCD" to the vehicle order, is covered under the terms of the BMW New Vehicle Limited Warranty for Passenger Cars and Light Trucks. Owners should not incur any charges for this service.

NHTSA ID: 11017504