I have a 04 530i sport.
Ok, So my radio hasn't been working now for a little bit (long story) and I was checking some fuses last night. As it is often times very difficult to see a burnt fuse, i was pulling the fuses. I have to assume that the alarm system is tied in with either the radio system or the iDrive. Well, I pulled and verified the fuses were all good for the various things that could be controlling the radio. To be specific, I had it diagnosed as a faulty logic amp, which has been replaced to no avail.
I know pulling the fuses prolly wasn't the best thing to do in the delicate environment of the iDrive system, but I did it and it's done now. Now my keys won't set the alarm or lock the doors... I'll go in with a high powered flash light later and check the fuses with them in place. My question is, if I pulled the fuse to the iDrive to verify it wasn't blown, does that require a re-programming of the keys? Or is it more serious and require I make a trip to my Indy to have error codes reset.
Also, the gas door is not engaging when locked manually. Got some fuses and will check the central locking fuse. If that's not it, then what's next??? trip to indy?
Because I can see someone asking, the car was parked, not running, keys out of the ignition.
Thanks for any help!!! I'll update later if I find anything that was blown or worked to resolve the issue.

 

If you have a voltmeter, test the battery voltage. I am guessing that the battery is low.
Or take the car to your local auto parts store, they can load test the battery and tell you if it's bad.

 

I would consider the battery except the battery is less than a month old... How about the Intelligent Battery Sensor (IBS) cable?