Is there a way to cheat on Xbox original games being played on an Xbox 360?

I bought a copy of doom 3 resurrection of evil to play on the 360 and have hit a spot at the middle of the game where I’ve devised a strategy to take down a guardian but at best I can only reduce its HP meter to 1/3 left before dying. I tried all of the cheats listed but they all seem to only work for the original Xbox. Is there a way to cheat on this game on an xbox 360? Any way at all? Because I’m enjoying this game and I don’t really want to scrap it or go out and buy a first gen xbox to play past this one level. Thnx in advance.

What cheat code did you use?
According to Gamefaqs, if you hold the left trigger, and press press X, Y, B, A while holding the left trigger, this should activate the god mode, making you invincible.