BMW 7 Series Key Dead? Dash Warnings Signal Battery Issue

Hey there! I had a similar issue with my 2003 BMW 5 Series last month. Got the same symptoms, keyless entry failed and dashboard warnings popped up. Changed the key battery myself, but the problems persisted. Took it to the garage and turned out the key's internal circuit was damaged from moisture getting inside. Had to get the key reprogrammed and some internal components replaced. It wasn't just a simple battery swap but wasn't a major repair either. The car was ready next day. Should mention though, while waiting at the garage, another guy came in with a 7 Series having similar issues, but his was just a dead battery in the key. Worth getting it checked professionally just to be sure. These systems are pretty complex and it's better to rule out any deeper issues. Best of luck with yours.

Thanks for sharing your experience! Sorry to hear you had to get the key reprogrammed. Would you mind telling me how much that repair ended up costing you? Also, has everything been working fine since the fix? Been worried about taking mine in since my last mechanic experience wasn't great, so trying to get a better idea of what I might be dealing with.

Hey again! Happy to report some good news on my end! Just wanted to update you, I actually got really lucky compared to what I initially thought. When I took it to the mechanic, it turned out it was just the key battery after all, despite my previous concerns about the internal circuit. The total bill came to 37€, which covered both the battery replacement and a quick diagnostic check. I know that might seem a bit steep for just a battery, but they also made sure everything was properly synced with the car's system. The best part? Since getting it fixed two months ago, I haven't had a single issue, no more warning lights, keyless entry works perfectly, and the "Battery in key empty" warning hasn't shown up again. Much better outcome than when I had to get my key reprogrammed with my old BMW! Regarding your mechanic concerns, totally get it. Maybe ask around in the BMW community for recommendations? Sometimes finding the right mechanic makes all the difference. Let me know how it goes with yours!

Thanks for the follow-up! Really relieved to hear your repair was simple and relatively inexpensive. You inspired me to just bite the bullet and get it checked out. Took it to a mechanic yesterday, turned out it was also just a dead key battery like yours! The funny part is I was stressing over nothing. The whole thing cost me about 40 bucks and took less than an hour. The mechanic even showed me how to check the key battery myself for next time. No more dashboard warnings, and my keyless entry is working perfectly again. What a relief after all that worry! Sometimes the simplest explanation really is the right one. Thanks again for your help, you saved me from spending days worrying about potentially major repairs!