BMW DTC P171C – Internal Transmission Control Module Watchdog Initialization Error
DTC P171C meaning on BMW
The DTC P171C on a BMW indicates an Internal Transmission Control Module Watchdog Initialization Error. This fault code is specific to the transmission control module and signifies a problem with the module’s initialization process.
BMW DTC P171C symptoms
Symptoms of the BMW DTC P171C may include erratic shifting behavior, transmission slipping, harsh shifting, or the transmission going into limp mode. The vehicle may also display a warning light on the dashboard indicating a transmission fault.
BMW DTC P171C causes
The causes of the DTC P171C on a BMW can vary, but common reasons include a faulty transmission control module, software issues, wiring problems, or internal transmission component failures.
BMW DTC P171C seriousness
The DTC P171C is a serious fault code as it directly relates to the transmission control module’s functionality. Ignoring this issue can lead to further transmission problems and potential drivability issues. It is recommended to address this fault promptly.
How to diagnose DTC P171C on BMW
To diagnose the DTC P171C on a BMW, a diagnostic scan tool capable of reading transmission fault codes is required. The technician will need to retrieve the specific fault code, check for any related codes, and perform a thorough inspection of the transmission control module, wiring, and related components.
How to fix DTC P171C on BMW
Fixing the DTC P171C on a BMW may involve reprogramming the transmission control module, repairing or replacing damaged wiring, or replacing the transmission control module itself. It is essential to follow the manufacturer’s diagnostic and repair procedures to address this fault correctly.
How to erase DTC P171C on BMW
Once the underlying issue causing the DTC P171C on a BMW has been resolved, the fault code can be cleared using a diagnostic scan tool. The technician can access the fault code menu, select the DTC P171C, and choose to clear the code. After clearing the code, it is recommended to test drive the vehicle to ensure 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
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