blown fuse no running lights

[towjo]

Just got the bike 1980 xs400 got it running and then the head light flickered and the fuse blew for the running lights. also the neutral light went out as well. now there is a direct short . i can unplug the wiring in the headlight that goes to the tach and fuse doesnt blow but still no running lights or neutral light. not sure as too what fuse it is due to previous owner removed the fuse box and wiried newer type fuses directly in line. any ideas would be great.. thanks

 

[bcware]

You'll have to figure this out on your own. It's hard enough to diagnose someone else's electrical problem when they have a stock harness; if yours is hacked up there is no way anyone can really help beyond providing very general advice.

Before you go crazy make sure your bulbs are actually working. Test them on a known good battery to make sure they haven't simply blown or burned out; it happens.

As far as general electric troubleshooting goes it is simply a patience game. You tackle it one wire at a time. Remove the gas tank and the seat and make sure nothing else was chopped up.

Looks for electrical tape and cheap connectors. If anything is touching the frame that shouldn't be you'll get a short.

 

[towjo]

the only thing that has been done to the wiring is the fuse box removed and newer fuses installed. all other wiring is not tampered with. the running lights and neutral lights did work till i saw the flicker of the head light then they all went out. i un plugged the head light and fuse still blew. as stated the first time with all lights hooked up i can unplug the three wire harness to the tach and all is fine. i dont have a wiring diagram yet just checking to see if anyone else ran across this problem and yes the lights are all tested and work.. any other ideas greatly welcome