All. first time posting here, this forum is great. I've searched around and found some references to the "blue wire fix" which was going to be my last resort.
My headlight too did not work. Last year, I futzed around with wires, checked headlight, didn't find anything wrong, and viola, it started working again, ugh. Stayed working until the end of the year.
This year, I put on new tires, lubed my drive shaft, got it all back together, and bam, no headlight again. Ok, something other than a stupid connector is to blame. I started digging, doing diode checks and relay checks on the junction box. Having been bit by the junction box BS once before (fan relay wouldn't engage, causing overheating, causing blown battery, ALMOST causing stator, but luckily for me, stator was fine).
Don't be afraid of that junction box, it is a piece of cake. Unscrew it, unplug the two connectors and take it out. Now my bike is a 1994, and the JB has 4 melted posts that hold it together. I simply drilled them out and then popped it right open (take out all the fuses first though). The pictures below shows what I did. The first time I got bit, the ribs on the back of the JB rubbed away circuit board traces!!!!! I had to solder in new wires to replace the lost traces and shave down the offending ribs with a knife. Fan problem solved.
This time was a bit more evil. Checking the diodes from the connector, sometimes one would work, sometimes not. UGH. checking the diodes right on the board, perfect every time. Wierd. COLD SOLDER JOINT!!!!! I found that on pin 15, where it connects to the circuit board, if i looked real close, there was a crack in the solder! Lucky to find it! I simply resoldererd every connection point where each connecter connected to the circuit board, snapped it back together, remounted it, and HEADLIGHT FIXED!!!!
I guess after 17 years, that junction box gets its share of wear and tear, but the insides are grade school electronics, not much in there to fail, other than the circuit board itself!!!! I'm uploading pictures, next post will show what I mean. Bottom line, tear into the junction box, it is pretty simple.
EDIT: reading KM60155 in the last post..... The headlight only comes on after the first time you push the start button (at least on my '94). It stays on if you turn off the bike. It turns out if you try to restart the bike, while the starter is pushed in. So, first time you turn on your key, light is NOT on. After you start, light on. If you turn your run switch off, light still on.
Last edited by prijo; 03-27-2011 at 06:42 PM.