I dont know if this is the same problem but this has happened to me 3 times in the last 2 weeks at my home address, It has affected both of my cars (Mercedes SLK and Lexus RX.
Also at the same time my electric gates and electric garage doors also stopped working.
I have 2 fobs for the cars and the garage/gates and none of them worked, After about 5 or 6 hours everything starts to work again but by this time I had all ready replaced all the batteries to no effect,This issue needs addressing and soon, i have found out that radio signals can block key fobs
james
April 2008