Why is my PlayStation 3 not showing color?

My PS3 hasn’t been on for a little while from a black screen issue that was resolved by rebuilding the database. Now that I can see the screen though, it is only showing in black and white. I’ve looked at settings and updated it to match our new monitor setup (the three cables-red, white and yellow- from one main cord, forgot the name) into a 480i screen. I have the RGB full range setting set to limited (changing this setting did not do anything), and deep color output on automatic, if that helps. I have updated it, but that didn’t work either. Could someone help me?