Audi Q3 Keyless Entry Failure, Common Door Handle Fix

I had a similar door sensor issue with my 2019 Audi Q2. With some experience working on car electronics, I first thought it was the key fob battery, but the diagnostic showed problems with the door electronics. The workshop found that the cable connection between the door handle sensor and the main door electronics unit had become loose over time. The electric door system would intermittently fail to recognize the key fob presence. After checking all connections, they discovered a damaged wire in the door handle assembly. The repair involved replacing the faulty wiring harness and testing all door sensor connections. Total cost was 95 Euro including labor and parts. Since the fix, the keyless entry has worked flawlessly. For your Q3, could you share: Does this happen on all doors or just one specific door? Are there any other electrical issues like window controls or mirror functions? Does the key fob work normally for locking/unlocking with buttons? Have you noticed any water damage or exposure that might affect the door electronics? This information would help determine if your issue is similar to what I experienced or potentially something different.

Last service was completed at 65000 KM, about 2 months ago. The issue occurs on all doors and the key fob buttons work normally. No water damage visible and all other door functions like windows and mirrors operate as expected. It seems the car door handles simply fail to detect the key fob presence when approaching. The locking system behaves inconsistently, sometimes working for a few attempts before failing again. Based on your feedback about the wiring harness, this sounds very similar to my car door problem. The workshop quoted much higher at 450 Euro though, claiming the entire door handle sensor unit needs replacement. Currently at 68870 KM and looking for a second opinion before proceeding with such an expensive repair.

Thanks for the additional details about your Q3. Based on those symptoms, I suspect you might have a simpler issue than my Q2 case, despite the similar behavior. The fact that all doors are affected simultaneously points more toward a central door electronics control unit rather than individual door handle sensors failing. The door actuator and sensor system uses a central control module to coordinate all door handles. When my Q2 had issues, it was specific to one door, which made the wiring harness the obvious culprit. Your case showing all doors affected suggests the main door electronics module might need recalibration or replacement. The 450 Euro quote seems high if they are planning to replace door handle sensors without first checking the central control unit. In my experience with Audi door electronics, the handle sensors rarely fail across all doors at once. Before proceeding with expensive sensor replacements, request they specifically check: Central locking system control module function, Key fob signal strength at each door handle, Door handle sensor voltage readings The inconsistent behavior you describe matches a failing control module more than faulty door handle sensors. This could potentially be a much simpler fix than replacing multiple sensor units.

Thanks for the detailed response. I will definitely request those specific checks before agreeing to the sensor replacements. The explanation about the central control module makes more sense given how the issue affects all doors simultaneously. I called another workshop and they quoted 280 Euro for a full diagnostic of the door electronics and control module, including recalibration if needed. This seems more reasonable than jumping straight to replacing multiple door handle sensors for 450 Euro. My next step will be booking the diagnostic at the second workshop and having them check the central locking control module first. The inconsistent behavior definitely matches what you described about control module issues rather than individual door actuator problems. Will update once I know more about the actual wiring fault or control module status. For now, I can live with using the key fob buttons manually while waiting for the proper diagnosis. At least all other door mechanism functions are working normally.