Key fob battery

[Annac1988]

I bought a Toyota Yaris 2007 a few months ago with a keyless key fob. This week it wouldn’t unlock the car or switch on the ignition so I used my other key fob which worked fine until yesterday when it wouldn’t work either..

I figured it was a Battery issue so replaced batteries in both key fobs. However, when I press the unlock button now on both key fobs and won’t unlock the car or start the ignition. 
 

Any ideas? 

[HughA]

Replacement batteries faulty or incorrectly fitted perhaps? Some key fobs have a red LED that flashes when you press a button.  If yours have the LED that will tell you if the Battery is OK.