Main beam problem?

On Sunday I was out riding and got caught in a thunderstorm, when I pulled over to change gloves I stopped the engine. When I started up again I noticed main beam light on I pressed the passing switch several times and nothing happened, it stayed on. Going about a hundred yards main beam light went out, but came on once or twice, on the way home. When I got home I though water had gotten into the handlebar switch, so sprayed WD 40 into it. Today I went to fill up with fuel for my ride out, after putting fuel in, on starting up main beam light on again stayed on till I went over a bump in the road then went out and all was back to normal. I thought wiring was just from switch to headlight, is there another connection elsewhere I should check ? anyone had this problem?

There are several wire harness connections for the lights. The main headlight / front turn signal harness has a brown 9 pin connection. It's the one which you disconnect when you remove the Front Cover (fairing).  

There are two connections for the left handlebar switches; one black 9 pin, and one red 6 pin. They are inconveniently tucked in under the handlebar covers and below the Combination Meter

There is one red 9 pin connection for the right handlebar switches --also below the CM

Best suggestion I have is to check continuity on the B/R to Bu/W wires of the red 9 pin connector for the right handlebar switch harness. That circuit should be CLOSED when the push to Start switch is in the rest position, and the circuit OPEN the Start switch is activated. When the Start switch is activated the OPEN B/R Bu/W circuit kills the current to the headlight.

It is possible that the Start switch terminals are dirty or corroded and that is what is causing the headlight to act erratic.

But first try a 'quick 'n dirty' test; give the right handlebar switch a good whack with a screwdriver handle when the headlight craps out. If the light comes back ON then...

My 2¢ opinion. HTH

EDIT: I should note that our North American FSC models don't have the "flash to pass" circuit like the UK FJS models.

Tim

Keeping it simple---try another standard bulb.

john grinsel wrote:

Keeping it simple---try another standard bulb.

I'm working from Honda CAR experience here. Headlamp is always powered and works through the ground side. Needs to ground to come on. Try a bulb first filaments could be shorting making that ground.

Thanks for all advice, will try new bulb first as suggested. Tinkering later today. Must admit i would not have thought bulb was the problem.

I changed the main beam bulb as suggested, the old bulb appears okay but, that does not mean it is, time will tell if that was the problem, thanks again for all advice.