Electrical woes-no current

[toucheturtle]

Hi,

I rode my CB500 today as usual and turned the engine off with the ignition key. The headlight and indicator were on when I switched the ignition off. When I came to restart it there was no electrical power to any part of the bike.

I assumed it must have been the main fuse. On checking it I discovered it had a 30amp rather than 15amp fuse (which I have now replaced with the correct one) but it was intact.

My bike is a K2 Italian import with later type wiring housing three fuses in the fuse box, a 7amp, 5amp and 15amp fuse-all OK.

I haven't performed any recent electrical modifications and cant figure out why I don't get any electrics at all. No warning lights, horn etc. The battery is healthy and I continuity to the solenoid through to the ignition switch. I have continuity across the red/yellow and green/red wires of the solenoid. The kill switch is obviously in the RUN position

I have continuity from the starter button switch to the block connector under the seat for both wires.

With the red/yellow and green/red wires disconnected leading from the solenoid and the ignition on and the starter button depressed-there is no continuity between the two large contacts on the top of the solenoid.

Is the solenoid at fault or am I barking up the wrong tree?

Many thanks,

Andy

[florence]

I have had this happen twice and both times it was the ignition switch at fault, the second time the switch was NOS.  See if you can wiggle the switch barrel about.

One time it happened going along in the dark; lights out, engine out, very scary.

In the end replaced ignition switch with one from an Austin A35 car.  Much better.

[toucheturtle]

Have played with ignition switch, took it out and sprayed it with WD40, put it back and jiggled it, made no difference 

[florence]

OK but really one would need to check continuity between the terminals at the back of the switch where the wires are soldered on. 

I am sure you are right and it is something else but you never know....

[toucheturtle]

I appreciate the advice and I'll check the continuity tomorrow, I've got to go in to work now. Do you know which wires I should check?

[Bryanj]

You need a muti meter or a bulb with leads and clips, put the neg of the meter, or one lead of the bulb, on the neg of the battery then test for power with the other lead starting at the fuse then going through the loom contact by contact, be methodical and don't jump backwards and forwards or you will end up chasing your ar*e till you dissapear in a puff of blue smake

[toucheturtle]

Have just got the multi meter out, there is no 12v current out from the red/yellow or green/red wires from the solenoid. If I turn the ignition to park just the rear light and front side light come on but it wont with the ignition switched on and with the light switch on.

[matthewmosse]

easy way to check the ignition system has power and the earth, stick a insulated screwdriver accross the big soilnoid terminals (bike in nueutral for this one boys and girls) (wonder why a cheap insulated screwdriver then try it - the spark will take a chunk out of it but you'll know if the starter switch and ignition system are playing ball as well as the earth (battery to frame) and battery too. I had onne battery go inside a terminal intermittently leaving the  bike dead and then comming back to life apparently randomly - took an age to figure that one out!.

[toucheturtle]

I've been all over the wiring today only to discover horrible bodges here there and everywhere. I've now got 12 volts going to the 15amp fuse and the 5amp parking lamp fuse but cant get it to the 7amp headlight fuse. Have 12 volts to the red wires to the back of the ignition and seem to have continuity all along the red/green and brown/white circuits. I'm not sure if something might have blown?

When you turn the ignition to park you can hear a slight click from the solenoid but turning it to on it does nothing. Where should I test the voltage after the ignition switch?