Audi A2 Central Locking Failure: Fix Guide

Having moderate experience with Audi electronics, I faced an almost identical central locking issue on my 2005 Audi A3 last year. The keyless entry system completely stopped responding, and the key fob became unresponsive overnight. The problem turned out to be a damaged wiring harness connection near the driver's door, which affected the entire central locking system. After some diagnostic work, the workshop found that moisture had corroded one of the main connection plugs, breaking the circuit. The repair involved replacing the damaged wiring section and connector, plus reprogramming the central locking module. Total cost was 95 Euro, including labor. The fix took about 2 hours, and the system has worked flawlessly since. Before suggesting specific solutions for your A2, could you provide: Does the key fob battery show any signs of life? Are all doors affected equally? Can you hear the central locking pump working when attempting to lock/unlock? Have you noticed any previous intermittent issues with the car alarm or door locks? This information would help narrow down whether you're dealing with a similar wiring issue or possibly a different component failure in the central locking system.

Last service was done at 12268 KM and they did check the door locking mechanisms. The car alarm system worked fine back then. Your experience sounds very similar to what Im dealing with. I just checked and noticed some moisture around the driver door wiring. After reading your reply, I inspected the keyless entry system more carefully and found corrosion on the connector pins in the door frame. The key fob still lights up with a fresh battery, but the central locking doesnt respond at all. The remote locking completely failed on all doors simultaneously. The door locks still work manually, suggesting the mechanical parts are fine. I cant hear the central locking pump working when using the key fob, which might point to an electrical connection issue rather than a mechanical problem. Would it make sense to first try cleaning the connector pins before replacing the entire wiring harness?

This is exactly what happened with my A3. If you can see visible corrosion on the connector pins, cleaning them might provide a temporary fix, but in my experience, its not a reliable long-term solution. The corrosion usually extends deeper into the wiring harness than whats visible. The symptoms match perfectly, silent locking pump, working mechanical locks, and simultaneous failure across all doors points directly to a wiring issue affecting the central locking system. The security system likely cant communicate properly with the door lock actuators due to the damaged connections. I initially tried cleaning my connector pins with electrical contact cleaner, but the problem returned within weeks. The proper fix required replacing the affected wiring section because moisture had traveled along the copper wires inside the insulation. Since your car shows the same signs mine did, Id recommend: 1. Getting the wiring harness connection replaced 2. Having the security system checked and recalibrated 3. Ensuring all door seals are intact to prevent future moisture issues The repair should cost similarly to what I paid (around 95 Euro), assuming the damage is limited to the wiring harness and hasnt affected the central locking control module itself. Has water been getting inside the door panel? This could indicate worn weather sealing that needs attention to prevent the problem from recurring.

Thanks for sharing those details about the security system and your analysis of the corrosion. Looking at my door panel more closely, I can see water marks inside, suggesting the door seals might indeed be compromised. Based on your experience, I agree that just cleaning the connector pins would likely be a temporary band-aid. The simultaneous failure of the central locking and the silent locking pump definitely point to deeper wiring issues in the security system, just as you encountered. The fuse box appears undamaged, but I think Ill go ahead with replacing the wiring harness section and have them check the door seals while theyre at it. The quoted repair cost of around 95 Euro for the wiring work seems reasonable, especially if it includes recalibrating the keyless entry system. I appreciate you mentioning the importance of checking the weather sealing too. No point fixing the wiring if water can still get in and cause the same problem again. Ill make sure to have them do a thorough inspection of all the door seals during the repair.