Audi Q5 Door Lock System Complete Failure at 30k km

Had the same central locking issue on my 2014 Audi Q3 2.0 TFSI. The key fob signals were not being recognized by the security system control module. After diagnosis, it turned out the main wiring harness connecting to the door control unit had corroded connector pins. The problem started similarly, complete failure of keyless entry and remote locking functions across all doors. The car security system showed a fault code pointing to communication issues with the door modules. This required removing door panels to access and replace the damaged wiring harness and clean the connector pins. While not a complex repair for experienced techs, it needs proper diagnostic equipment to verify the security system is communicating correctly after the fix. A failing door control module or blown fuse in the central fuse box can show similar symptoms, but the wiring harness issue is more common in these models. Would recommend having a certified shop check the wiring connections first before replacing more expensive components. The repair was significant enough to require specialized tools and programming to restore full functionality of the car locks and security system. Note: Your Q5 likely has updated wiring compared to my Q3, but the general diagnostic approach would be similar.

Thanks for sharing your experience with the door locks issue. My Q5 started working properly after the repair, but I am curious about your repair costs. Would you mind sharing how much you paid? Also wondering if youve had any other issues pop up with the keyless entry or security system since getting it fixed? Always good to know what to watch out for with these electronic systems.

Thanks for asking about the repair costs. Got my door locks issue fully resolved by paying 95 Euro at the shop. The mechanic found and fixed a faulty cable connection in the car alarm system. Since the repair, the central locking and key fob functions have worked flawlessly, no more problems with the keyless entry or security features. The technician mentioned that regular cleaning of the door lock mechanisms can prevent similar issues. The car alarm system components are sensitive to dirt and moisture, which can affect the connections over time. But honestly, in the two years since the repair, I havent needed to go back for any related problems with the central locking or security system. My advice would be to keep an eye on how smoothly the locks engage, any hesitation could be an early warning sign of developing issues with the connections in the fuse box or door control modules.

Thanks everyone for the helpful responses. I finally took my Q5 to a new mechanic who specializes in European cars. The door locks issue ended up being caused by a failed control module, which was more expensive than the wiring problem others mentioned. Total repair came to 480 Euro including parts and labor. The good news is the remote locking and keyless entry work perfectly now. The mechanic actually showed me the corroded module after removing it. He mentioned these electronic locking mechanism failures are fairly common in humid conditions. Much better experience than my previous shop visit. The new tech took time to explain the car alarm system components and how they work together. For anyone facing similar issues, definitely worth finding a specialist who knows these security systems well. Just glad to have working door locks again. Will keep monitoring for any quirks with the keyless entry, but so far everything is functioning as it should.