It could still be the fob battery, they may be rechargeable but 13 years life with lots of charging or worse not using them and allowing them to flatten, is asking a lot of one.
Hi Buzzr666, just wondering how you made out with the battery replacement?iv the same problem as yourself, iv just got a mini one 2005, iv just ordered a new battery, BUT it needs de-soldering of the keyfobs circuit board and the new one soldering back on, when it arives il let youn know if it works.