03 S40, keyless entry not working

[casualcoma]

I've read pretty deep and couldn't find info for my specific car.
2003 S40, switchblade type keys.
Keyless entry stopped working, so I put a brand new battery in. Still doesn't work. My other remote also doesn't work, haven't changed that battery yet.
I'm not interested in going to the dealer.
Can I reprogram using the 5-times turning the key method?
I also understand there's a receiver or antenna that could've gone bad. Where would I find these? How do I check?
Thanks in advance…