[ctuna]

Are you sure that you wired the battery back up correctly .
Or the other guy did.
If you use battery back up when changing the battery on these
it blows stuff up.
Might not be the relay might be something feeding it.

I would also check the battery voltage , yeah I know you
said it was new but a low battery voltage can cause you
a lot of ghost problems

Don't take stuff for granted measure it.