BMW DTC P171B – Internal Transmission Control Module Watchdog Run Time Error
DTC P171B meaning on BMW
DTC P171B on a BMW refers to an Internal Transmission Control Module Watchdog Run Time Error. This error code indicates that the transmission control module has detected a discrepancy in the expected run time of a specific function within the module.
BMW DTC P171B symptoms
Symptoms of DTC P171B on a BMW may include:
- Transmission shifting issues
- Harsh or delayed shifting
- Transmission slipping
- Decreased fuel efficiency
- Illuminated transmission warning light
BMW DTC P171B causes
The potential causes of DTC P171B on a BMW can include:
- Internal transmission control module software malfunction
- Faulty transmission control module
- Electrical wiring issues
- Sensor malfunction
BMW DTC P171B seriousness
DTC P171B should be addressed promptly as it can lead to further transmission problems if left unresolved. Ignoring this error code may result in damage to the transmission components and potentially lead to costly repairs.
How to diagnose DTC P171B on BMW
To diagnose DTC P171B on a BMW, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the specific error code
- Inspect the transmission control module for any visible damage
- Check the wiring and connectors for any signs of wear or corrosion
- Perform a thorough transmission system scan to identify any related issues
How to fix DTC P171B on BMW
Fixing DTC P171B on a BMW may involve the following steps:
- Update the transmission control module software if applicable
- Replace the faulty transmission control module if necessary
- Repair any damaged wiring or connectors
- Replace malfunctioning sensors
How to erase DTC P171B on BMW
To erase DTC P171B on a BMW, the error code can be cleared using a diagnostic scanner. After addressing the underlying issue that caused the error code, the mechanic can reset the transmission control module to clear the code and turn off the warning light.
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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