E61 M5 remote fob not working

[wolfracesonic]

As, title the remote fob has stopped working, the valet key also doesn't function. It's not a comfort access model, so would I be right in thinking there isn't a battery for me to replace in the fob and the issue is likely to be on the car itself? I've Googled it and come up with scary terms like 'diversity antennae '. The car is under a Mondial warranty but I didn't want to look a numpty when the technician tells me to just put a new £3.00 battery in the fob.

[Stever]

I have an idea from the M6 that the fob charges up while it is in the dash slot and I was advised to swap key fobs over from time to time to keep both charged but have to admit I never do as all my other keys are on one fob!

Just found a youtube that shows you how to change here https://www.youtube.com/watch?v=J2mM7woeTWQ

It's not a rechargeable battery so it seems (a CR2032) so the above advice looks like garbage

There are some other youtube videos that are different to the above suggest you watch them all before doing anything

Edited by Stever on Wednesday 28th June 14:36

[wolfracesonic]

Ta for that, a bit more research seems to show the one I've got isn't meant to be opened up, we'll see how good my Mondial cover is!

[cosworth330]

When I had my E60 M5 2006 model the spare key fob stopped working ( coffin shaped fob ) BMW renewed it and Mondial paid. Mine was the earlier type where the battery wasn't replaceable but I was led to believe that the facelift examples had a different fob where the battery could be replaced.