Touareg Door Lock System Failure: All Doors Unresponsive

Had the exact same problem on my 2019 Tiguan last winter. As someone with moderate experience working on VWs, I initially thought it was just a door sensor issue, but it turned out to be more complex. The car alarm system was getting inconsistent contact signals from a damaged wiring harness near the driver side door latch. The door switch was actually fine, but the connection had worn out over time. The workshop found that water had seeped in and corroded some of the wiring connecting to the central locking system. The fix involved replacing the damaged wiring section and recalibrating the door sensors. Total cost was 95€ including diagnostic time. Since then, no issues with the central locking system. To help diagnose your specific case more accurately, could you share: Does this happen with both remote and manual key use? Are there any other electrical issues like window controls or mirror adjustments? Have you noticed any moisture inside the door panels? Did this start suddenly or develop gradually? These details would help determine if your Touareg has a similar wiring issue or if its something else in the door latch mechanism.

Last service was at 145000km and currently running fine besides this door issue. The issue you experienced sounds quite similar. On my car, the problem affects both remote and manual key operation. The window controls and mirrors still work perfectly, which made me initially suspect just the door sensors. However, your mention of the wiring harness corrosion is concerning since I noticed some condensation on the inside of the driver door panel last month. For others with similar problems, it might be worth checking if there are any signs of water ingress near the door wiring before assuming the door sensor needs replacement. The 95€ repair cost seems reasonable compared to a full door latch replacement. Will get this checked at the workshop soon, focusing on the wiring harness inspection first rather than jumping straight to sensor replacement.

Thanks for sharing those additional details about your Touareg. The condensation you mentioned inside the driver door panel really strengthens my suspicion about water damage to the wiring harness. When I had my Tiguan repaired, the technician showed me how water had created a similar condensation pattern before seeping into the wiring bundle. The vehicle doors were mechanically sound, but the corroded wires were interrupting signals between the door switch and the central locking system. I recommend specifically asking the workshop to: 1. Check the wiring harness rubber boots for tears 2. Test continuity in the door wiring connections 3. Inspect the car sensor grounds for corrosion Since your window controls still work, this helps isolate the issue to the central locking circuit rather than the entire door wiring harness. My repair cost stayed at 95€ because we caught it before the corrosion spread to other circuits. Good call on planning to check the wiring before replacing components. The car alarm system often acts up with water-damaged wiring, even when the door sensors themselves are fine. Keep us posted on what the workshop finds.

Thanks for the detailed follow-up info about your vehicle. Those functioning window controls and mirror adjustments definitely help narrow things down. The condensation inside my driver door panel lines up with what you described about water damage, so checking the wiring harness first makes sense. After reading about your repair experience, I feel more confident this could be a wiring issue rather than a full door sensor or latch mechanism problem. Will have the workshop focus their inspection on the points you mentioned, especially the harness boots and wire continuity. The working mirrors and windows do suggest its isolated to just the central locking circuit. I particularly appreciate you sharing the repair cost details. At 95€ for diagnostics and harness repair, that seems much more reasonable than having to replace multiple door latches or car alarm components. Hopefully catching this early before the water damage spreads will keep the repair costs similar. Will book the workshop appointment this week and ask them to thoroughly check the wiring connections before replacing any parts. Thanks for helping point me in the right direction on diagnosing this automatic locks issue.