This is probably gonna sound remedial but did you check the fuses and the wiring for any shorts/blown fuses? If you had a bad gauge and replaced it and its still not working, I would assume its probably a wiring problem. Also what kind of gauge did you replace it with, someone once said that a 9c gauge wouldn't work with a civi car because of the blackout option or something, idk as I never owned a 9c1. I'd pull every fuse just to look, also check the relays. Maybe just a pinched wire in the harness left connector B2 is the ign feed (pink wire) the ground is B3 (black) on the right connector the ign feed is located @ A5 (brown wire) and the ground is A6 (black and white) and also B4 (black). I'd start there!