BMW DTC P171A – Internal Transmission Control Module Watchdog General Error
DTC P171A meaning on BMW
DTC P171A on a BMW refers to an Internal Transmission Control Module Watchdog General Error. This diagnostic trouble code indicates that the transmission control module has detected a general error related to its internal monitoring system.
BMW DTC P171A symptoms
Symptoms of DTC P171A on a BMW may include:
- Transmission shifting issues
- Harsh or delayed shifting
- Transmission slipping
- Reduced fuel efficiency
- Illuminated transmission warning light
BMW DTC P171A causes
The potential causes of DTC P171A on a BMW can include:
- Faulty transmission control module
- Internal transmission control module software issues
- Electrical wiring or connector problems
- Transmission fluid issues
BMW DTC P171A seriousness
DTC P171A should be addressed promptly as it can lead to further transmission problems if left unresolved. Ignoring this error code may result in more severe transmission issues and potential damage to the transmission system.
How to diagnose DTC P171A on BMW
To diagnose DTC P171A on a BMW, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes stored in the transmission control module.
- Inspect the transmission control module for any visible damage or signs of water intrusion.
- Check the transmission fluid level and condition.
- Conduct a thorough inspection of the electrical connectors and wiring related to the transmission system.
How to fix DTC P171A on BMW
To fix DTC P171A on a BMW, the following steps may be taken:
- Address any underlying issues identified during the diagnostic process, such as repairing or replacing a faulty transmission control module.
- Update the transmission control module software if necessary.
- Repair any damaged wiring or connectors in the transmission system.
- Ensure the transmission fluid is at the correct level and in good condition.
How to erase DTC P171A on BMW
After addressing the root cause of DTC P171A on a BMW, the fault code can be cleared using a diagnostic scanner. This will reset the transmission control module and turn off the warning light. It is important to verify that the issue has been resolved before clearing the fault code.
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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