Fj dies when hot.

[PolskiFJ]

This seems similar to the same issue that Dreadrock is having, but i know that It's not my ignition box. I have interchanged two of them thus far and i still get the same problem. Every time the bike gets hot, it dies, sometimes even just a half mile out of my driveway. My harness was looking rough so i put in a clean one from my parts bike. all the connections are good. At times I will lose running electric current altogether. Incredibly frustrated, as the last two weekends i pulled out the bike thinking it had been fixed only to break down a mile or two away from the house. It will start back up again on occasion, but most times it will shut off again immediately and i will crank it until the battery dies and call a friend to pick me up. What is the next move? desperately looking for some guidance. I'm at the point that if i cant get it fixed by mid august i'm going to take a sledge hammer to it. 

[Pat Conlon]

Help us help you. What model do you have?
With a new(er) harness and tight connections, it sounds like you can rule out the wires and connections, so that leaves the switches. Have you isolated (jumped) the sidestand switch?
When you say that you lose "running electrical current" what do you mean?
Checked the off/on switch on the handlebar? Checked the keyed ignition switch?

[PolskiFJ]

I have a 1984. What i mean by it, is that the bike, even when the key is turned to the on position will appear to be dead. This goes away when it cools down. I haven't checked the side stand switch, but i know that my ignition switch and on off switch work properly and are tightly secured. I'm just looking for a few things to check on the weekend.

Thus far things i know i need to check are

ignition coils
sidestand switch.


Does anyone else have and suggestions??

[simi_ed]

Try looking at the wire around the steering head, connected to the ignition switch.  My dad's `90 wouldn't shut off with the key!  He either had to use the kill switch or the clutch (in gear) to kill it.  He eventually found several wires melted together at the st. head.  All better now.

[PolskiFJ]

That can't be it. I traced the harness and all of the wires coming off it. The old harness had a few melted wires but this one looks great.

[oldktmdude]

  Check your fusebox under the LHS fairing panel. I had an issue with corrosion on the fuse holder that caused complete shut down when the connection became hot. Once it cooled, power returned temporarily then heated again and cut power. You may have a similar problem. Hope this helps. Regards, Pete.

[ribbert]

Aaaargh, intermittent electrical problems - 2 days to find, 2 minutes to fix! ( I assume you have eliminated fuel as the cause)

While the age of our FJ's can cause some electrical issues, melted wires isn't one of them.  I would think if I found melted wires I was well on the way to finding the problem.

Some things to try:

Temporarily hot wire the coils, that will eliminate most of the wiring, and take it for a ride.

With tank and inner panels off and temporary fuel supply, leave the bike idling and push, pull, tug, twist, poke etc all the wiring from one end to the other and see if it misses or cuts out as you do so.

Isolate switches one at a time and test ride.  This can be done with a short piece of wire or a small split pin but make sure it doesn't earth out.

In one of its "failed to proceed" moments, start tracing wires that should be live with a test light.

A test light with a very sharp pointy end is great because you can poke it through the insulation.

The list of causes I've found over the years for such problems would fill a book and apart from a few known make and model problems, it's always something different.  In this case though I would think the melted wires would be an obvious starting point.

Good luck

Noel