At some point the alternator shorted out causing a trace on the printed circuit for the tach to burn in two. I ran a jumper wire thinking it would bypass that. It still doesn't work. The tach responds at times but only burys itself to 0 or redline. also i took the alternator off and had it checked and it works just fine. Anyone got any ideas what could be the problem? Also I installed hid headlights for the low beams and when I go to turn the brights on the hids shut off and the original brights come on instead of both being on when the brights are on.what could cause this?