BMW iX3 Immobilizer Issue Preventing Start-Up

Hey there! I had a similar issue with my 2019 BMW i4 last year (I also own an iX). I've got some experience working on cars, but mostly basic maintenance stuff. The symptoms you're describing sound exactly like what I dealt with. The immobilizer system was acting up because of a programming issue with the key. Took it to my regular workshop, and they had to reprogram the key to sync properly with the car's system. The whole thing cost me 45 Euro and took about an hour to fix. Could you share some more details about when this started happening? Like, did it occur after changing the key battery or after any electrical work? Also, are you using the original key or a spare? This info would help pinpoint if we're dealing with the same problem. Quick tip: Make sure you're keeping your key away from other electronic devices when starting the car, as this can sometimes interfere with the signal.

Thanks for sharing your experience. I've also been dealing with this issue since yesterday morning, completely out of the blue. I'm using the original key fob, and I haven't changed the battery or had any electrical work done recently. My iX3 has 95193 KM on the clock and was just serviced last month. What's interesting is that when I tried using my spare key, I got the same result. Tried all the usual tricks like holding the key right up to the steering column and making sure there weren't any other electronic devices nearby, but no luck. Think I'll have to get it checked at the workshop, seems like it might be more than just a key programming issue in my case. Did your mechanic mention any other potential causes when they fixed yours?

Hey again! Yeah, when my mechanic worked on my i4, he actually mentioned a few other potential causes since I was curious about what else could trigger these symptoms. In my case, it turned out to be the key programming, but he said these issues can also pop up due to a faulty key reader in the steering column or problems with the immobilizer control module itself. Since you're getting the same result with both keys, it's probably not a key-specific issue like mine was. The fact that your car was just serviced last month makes me wonder if something got disconnected or disturbed during the service. My mechanic told me that sometimes the immobilizer system can get cranky if any related components are moved around or if there's been any work done near the electrical systems. You know what? Given that both keys are acting up, I'd put my money on either the key reader or the immobilizer module being the culprit. When they fixed mine, they actually tested both these components before zeroing in on the key programming issue. Let us know what they find when you get it checked out, I'm really curious to hear what's causing it in your case. These BMW electronics can be tricky sometimes!

Thanks everyone for the helpful responses! I just got back from the workshop and wanted to update you all. Turns out it was indeed the key reader in the steering column that was faulty. The mechanic found that some moisture had gotten into the unit and corroded a few connections. They replaced the entire reader assembly and recalibrated the system. The repair was a bit more expensive than just key reprogramming, cost me about 400 for parts and labor, but at least the car's running perfectly now. They also checked the immobilizer control module just to be safe, but that was working fine. It makes sense now why both keys weren't working! Really appreciate everyone's input, especially for sharing their experience. Even though our issues turned out to be different, your suggestions helped me better understand what to expect when I took it in. I'm just glad to have my car back and running properly. Hopefully this info helps anyone else who runs into similar problems with their BMW!