String issue with Key Fob

[DoubleDutch1962]

Can someone suggest what could be wrong with my key - this sequence happened 3 times with 3 different batteries now so I don't suspect it's the battery
key.jpg

• I replaced the battery in my key fob with a new Duracell one
• Fob works to open/close the car
• I leave the car for a week, try to open the door again and the "Zapper" doesn't work anymore. The red light on the key flashes (not sure to the same strength but it does flash)
• I then need to open the car with the key (and the alarm goes off)

Any thoughts on what could cause this? Bad contact / key broken?

Thanks in advance

[FrenchAudi]

Maybe a fault in the fob is draining the battery. Does it work if you fit one of the old batteries?

If not, and it works with a new battery, you probably need a new fob.

Edit: Another thought - maybe the pushbutton on the fob is not releasing the contact, so it draws current all the time. I don't know if you can get it apart to check this.