TATTY
You have mentioned two key facts:
1 The R-Mod has worked up to now
2 You can't play anything
May I suggest you try two things if you haven't done so already:
A Check that the R-Mod cables haven't popped out and/o the topside jumpers haven't come off.
B Take the R-mod out and reinstate to original condition.
If it doesn't work in original condition, then find your warranty sticker and put it back on, take the PS2 back.
If it works, get a Messiah/Clone. Save up for it if you have to - but that is the v5 chip to have.
Good repairers are in Stoke-on-Trent.
www.kanection.co.uk