VW Transporter Bluetooth Call Audio Failure Fix Guide

Similar issue occurred with my 2016 VW Multivan. Had limited experience with infotainment repairs, but this audio input problem was quite specific. After multiple troubleshooting attempts, the workshop discovered the voice recognition module was failing. The ambient noise cancellation feature was completely dead, making phone calls impossible despite having a working Bluetooth connection. Sound quality tests showed the microphone was receiving power but not processing audio correctly. The complete repair included: Full diagnostic scan, Testing microphone signal paths, Replacing the voice control module, Recoding the infotainment system, Testing all audio functions Total cost was 815€ and took about 4 hours to complete. The sound quality returned to normal after the fix. To help diagnose your specific case, could you share: Does the voice recognition for other functions still work? Are there any other electrical issues? Did this start suddenly or gradually? Have you had any recent electrical work done? This could help narrow down if your issue is similar or points to different components needing attention.

Had my 92044km service just last month, and the mechanic ran a full system check during that time. After several tests with my phone and the car audio system, I discovered the volume control for calls works fine, but the mic itself remains completely silent. All other Bluetooth functions like music streaming work perfectly. The hands-free feature just stopped working one morning with no warning. The main diagnostic codes point to a microphone fault, but given how the Bluetooth issue appeared so suddenly, I suspect it might be a wiring problem rather than the mic itself. The ambient noise cancellation test in the workshop also failed completely. Would getting the wiring checked first make sense before replacing the entire microphone assembly?

Thanks for those additional details. Based on your description and comparing it to my VW Multivan experience, this does sound more like a wiring issue than a complete microphone failure. The sudden onset without warning, combined with working volume control but complete mic silence, matches what happened before my module replacement. However, your case shows some key differences: The fact that ambient noise cancellation failed but other wireless connection features work points more toward the wiring harness between the microphone and the voice recognition module. In my case, all audio input functions failed simultaneously. Recommended diagnostic steps: Check the wiring connectors at the microphone first, Test the voltage at the mic connection points, Inspect for any pinched cables in the headliner, Run a full audio system diagnostic My complete module replacement might have been overkill for what could have been just a wiring issue. Starting with a wiring inspection could save significant cost versus immediately replacing components. Since this started right after service, have the workshop check if any connections were accidentally disturbed during maintenance. A loose connector could explain the sudden failure while preserving other audio functions.

Thanks for the input. This really helps narrow things down. Based on the experiences shared, I will have the workshop inspect the wiring first before considering a full microphone replacement. The voice recognition issues and ambient noise problems definitely point toward a connection problem rather than hardware failure. Since the sound quality is fine for music and the Bluetooth connection remains stable, focusing on the wiring between the mic and module makes the most sense. I will schedule the diagnostic inspection and have them specifically check: All wiring connections near the recent service areas, Voltage testing at the microphone points, Full audio input system scan, Connection points in the headliner Will update once the workshop completes their inspection and determines if its just a wiring fix or if module replacement is actually needed. Hoping for the simpler and less expensive solution. Thanks again for helping me avoid potentially unnecessary parts replacement.