benh116

I just recently bought a 2005 545i. It came with only one key and that was a normal diamond style key with working lock and unlock buttons. Because I only had one key I had to buy another and decided to buy 2 upgraded flip keys. I went to a key place and they cut the key, put a new chip in it because the old one wasn't working, and then programmed it and now it can start the car like its supposed to with no issues. Everything works fine except the buttons on it, the lock, unlock, and trunk button don't actually do anything and he tried all the sequences to get it connected but it didn't work and when he gave up I spent hours doing research and hours trying all the sequences I could find online. Eventually I gave up with that and decided maybe it was something wrong with these keys so I bought two more from a different seller on Amazon and looked at tons of reviews that said it was great but when I tried all the sequences and everything on those two they didn't work either. I've tried everything I could think of and now I have 4 keys lying around with buttons that don't work. Its not the batteries, there's a light that flashes when I press buttons. The two new ones aren't cut and programmed and I didn't want to waste money if it wasn't gonna work, so I was doing part of the sequence with the old working key and part of it with the new one similar to this ( ) but with a different new key. I have no idea what to do, if anyone has any ideas that would be great, Thanks!

benh116

Okay so i've never used this website before and apparently really messed up the formatting by putting a link there, sorry

Erik Sierra

Are you sure you bought the new keys with the correct radio frequency? For example mine is 315mhz but they were also made with 868 mhz. Try opening your original diamond style key and look in the back of the motherboard for the frequency

You can see on the right side that mine says 315 also I looked up my VIN and the same thing came up


Look under radio frequency

donpb

Umm you bought keys off of eBay? I dunno about that.

The chip is used to start the car but the buttons use radio frequency.

Erik Sierra

I bought the keys off of Amazon so I assume they are very similar to those found in eBay. And yes, of course the remote uses radio to open the doors so if your remote doesn't have the same frequency as your car then it won't pick up any signal

benh116

I cant find a VIN lookup site that tells me the frequency but on the original diamond key it says 315 MHz on the back and both sets I bought from amazon and eBay also said 315

donpb

There's probably more to it than just simply matching the frequencies. Could be a compatibly issue with that particular key.