Battery woes !

[Nattyboy888]

Found my wife's old tag f1 in a draw. Thought I'd try and replace the battery and let my daughter use it. Ordered an SR626 battery as per the one that came out, but where the old one was quite tight, this one is loose. When pressed in the movement works fine, but when I try to secure it, it starts jumping every 5 seconds.

are there different types of this battery - they look the same but they are very small obviously so there may be subtle differences ?

any help appreciated

[Nattyboy888]

Brilliant advice - thanks very much. I confess the battery was in a blister pack bought from the pound shop (but the expiry date was fine) - however tried your 'scrape' test and it's now working ! Only downside is I lost one if the strap springbats so eBay beckons I guess lol.