BMW DTC U0171 – Lost Communication With ‘Restraints System Sensor B’
DTC U0171 meaning on BMW
The DTC U0171 code on a BMW indicates that there has been a loss of communication with ‘Restraints System Sensor B’. This means that the vehicle’s onboard computer system is unable to receive data from this specific sensor, which is crucial for the proper functioning of the vehicle’s restraint system.
BMW DTC U0171 symptoms
Symptoms of the DTC U0171 code on a BMW may include the airbag warning light illuminating on the dashboard, potential loss of functionality of the restraint system, and in some cases, the vehicle may go into a limp mode to prevent any potential safety hazards.
BMW DTC U0171 causes
The most common causes of the DTC U0171 code on a BMW include a faulty ‘Restraints System Sensor B’, damaged wiring or connectors related to the sensor, a malfunctioning airbag control module, or issues with the vehicle’s onboard computer system.
BMW DTC U0171 seriousness
The DTC U0171 code should be taken seriously as it directly affects the proper functioning of the vehicle’s restraint system, which is crucial for occupant safety in the event of a collision. It is recommended to address this issue promptly to ensure the vehicle’s safety systems are fully operational.
How to diagnose DTC U0171 on BMW
To diagnose the DTC U0171 code on a BMW, a mechanic would typically use a diagnostic scanner to retrieve the specific fault codes stored in the vehicle’s computer system. They would then inspect the ‘Restraints System Sensor B’, check the wiring and connectors for any damage, and perform further tests to pinpoint the exact cause of the communication loss.
How to fix DTC U0171 on BMW
Fixing the DTC U0171 code on a BMW may involve replacing the faulty ‘Restraints System Sensor B’, repairing any damaged wiring or connectors, resetting the airbag control module, or reprogramming the vehicle’s computer system to establish communication with the sensor. It is recommended to follow the manufacturer’s guidelines and use genuine parts for the repair.
How to erase DTC U0171 on BMW
To erase the DTC U0171 code on a BMW, a mechanic would typically use a diagnostic scanner to clear the fault codes stored in the vehicle’s computer system. Once the underlying issue has been addressed and fixed, the code can be erased to reset the system and ensure that the fault does not reoccur.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.