BMW iX3 Keyless Entry Failure: Door Handle Investigation

Hey! I've got some experience working with EVs and had a similar issue with my 2019 BMW i4 (I also owned an iX before). I totally feel your pain! Had the exact same symptoms, keyless entry failing and those annoying fault codes. Turned out to be a loose connection in the door handle wiring harness. Took it to my workshop and they found a damaged cable that was causing intermittent connection issues. Fixed it for 95 Euro and it's been working perfectly since. Before I can give you more specific advice, could you share: Have you noticed any other electrical issues? Does it happen on all doors or just one? Have you checked if the key fob battery is good? Let me know these details and I might be able to help you narrow down the problem.

Thanks for sharing your experience! Mine's at 156297 KM and had its last service just 3 weeks ago. They actually checked all the electronics then, and everything was fine. It's happening on all doors, and yes, I've already tried changing the key fob battery, but no luck. The weird thing is it started right after a really rainy weekend. Haven't noticed any other electrical problems though. The car runs perfectly fine otherwise, and the charging system still works great. Might take it back to the shop and ask them to specifically check that wiring harness you mentioned. Really hoping it's just a similar loose connection and not something more serious!

Hey again! Thanks for those extra details, that's really helpful. When you mentioned it started after a rainy weekend, that immediately rang some bells for me! My i4 had a similar experience after heavy rain, and it turned out water had gotten into one of the door handle connectors. These cars are usually pretty well sealed, but sometimes the rubber grommets around the wiring can deteriorate or shift slightly, letting moisture creep in. Since it's affecting all doors and started after rain, I'd bet you're dealing with water ingress somewhere. In my case, they had to dry out the connectors and replace some seals. They also applied some dielectric grease to prevent future corrosion. The whole job cost me about 200 Euro, but it was worth it. Given that your car just had service 3 weeks ago, maybe they disturbed something while working on it? Could explain why the seals might not be sitting quite right. I'd definitely get them to check the door handle wiring and seals, especially around the connectors. Just to add, if it is water-related like mine was, you might want to get it checked sooner rather than later. Moisture can cause more problems if left unchecked. Let me know what they find, I'm curious if it's the same issue I had!

Thanks so much for the detailed explanation! That water ingress theory makes total sense, especially given the timing with the rain. You're right about getting it checked quickly, I've actually booked it in for tomorrow morning. Called the service center and mentioned what you said about the water damage possibility and the seals. They seemed to think you might be onto something, particularly since it started right after that rainy weekend. It's really helpful to know about the dielectric grease fix too, I'll make sure to ask them about that. Come to think of it, during the service they did have to remove some door panels to fix a window regulator. Maybe they didn't get the seals back on properly. Really appreciate your help on this! I'll definitely let you know what they find, but I'm feeling much more optimistic now that it's probably just a moisture issue rather than a major electrical problem.