Now it looks like the problem was electrical

nortonmargie

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Bike has been intermittently shutting off while in full cry, as you Brits say. Suggestion was to clean out the tank breather.
Cleaned out the tank breather yesterday, bike ran beautifully on idle for about five minutes. Planned to go for a ride today. No lights/no ignition. Battery is fully charged and wiring to battery is tight. Working the kill switch does not help. Pulled several of the spade connectors under the console with the key, one at a time,and checked with multimeter. No current whether key is on or off. Assume I need to check the ignition switch and if that is good, start chasing wires.

I have no idea how to wire the bike to bypass the ignition switch

How do I check to see if the ignition switch is OK?

What about the kill switch?
 
Kill switch only affects ignition, not lights so no need to think about that right now. Master switch and of course, fuse are suspect but what model do you have (MK3?) and what ignition system?

Follow the Brown/Blue wire checking for battery voltage across it and ground.
 
Ign switch connections are detailed in the Workshop manual electrics section, as is the full schematics for your model year. Can be downloaded from this site, Resources section...direct link here:


To rig a bypass, locate where power comes into IGN switch (from the in line fuse off the battery negative usually), take that connection off the ign switch terminal, connect a test lead with simple on/off toggle switch, run from that switch to the power in to ign EI (ie the negative if bike is still positive ground) connection. This bypasses ign switch internals and the kill switch at same time. Also all lights/horn...so just a test to see it power gets to ign reliably

Ign switch can be taken apart and internal contacts cleaned, spacer/insulator re-furbished, but easier/more reliable to just replace with new.
 
Ign switch connections are detailed in the Workshop manual electrics section, as is the full schematics for your model year. Can be downloaded from this site, Resources section...direct link here:


It's an 850 Mk3, I believe, so that would be the wrong manual and wiring diagram.
850 Mk3:
 
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Bike has been intermittently shutting off while in full cry, as you Brits say. Suggestion was to clean out the tank breather.
Cleaned out the tank breather yesterday, bike ran beautifully on idle for about five minutes. Planned to go for a ride today. No lights/no ignition. Battery is fully charged and wiring to battery is tight. Working the kill switch does not help. Pulled several of the spade connectors under the console with the key, one at a time,and checked with multimeter. No current whether key is on or off. Assume I need to check the ignition switch and if that is good, start chasing wires.

I have no idea how to wire the bike to bypass the ignition switch

How do I check to see if the ignition switch is OK?

What about the kill switch?
Full cry? Or starting, run/idle? Accurate detail will help solve the problem faster.

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By "full cry" I mean headed down the freeway at almost 70 mph (the bike bump started itself, but that was not fun). The reason why nothing worked yesterday was because the main fuse blew. It blew (apparently-need to do some checking) because prior to turning on the ignition I made sure that the spade fittings under the console were tight to the spades. Apparently pulling the fittings on and off with the ignition off blew the fuse. I have replacement fuses and have ordered a new ignition - the problem may be an internal short that appears when the bike is running

I plan to spend Wednesday afternoon tracing the blue/brown wire
 
By "full cry" I mean headed down the freeway at almost 70 mph (the bike bump started itself, but that was not fun). The reason why nothing worked yesterday was because the main fuse blew. It blew (apparently-need to do some checking) because prior to turning on the ignition I made sure that the spade fittings under the console were tight to the spades. Apparently pulling the fittings on and off with the ignition off blew the fuse. I have replacement fuses and have ordered a new ignition - the problem may be an internal short that appears when the bike is running

I plan to spend Wednesday afternoon tracing the blue/brown wire
It may possibly be 2 problems...being a possible fuel tap oring/filter issue...with a now identified electrical issue ?
Did you check fuel flow from the petcocks/taps ?
 
Apparently pulling the fittings on and off with the ignition off blew the fuse.

If the brown/blue wire terminal when removed had shorted to earth/ground then the fuse would have blown regardless of the switch position so it's possible you inadvertently caused the fuse to blow.
 
If the brown/blue wire terminal when removed had shorted to earth/ground then the fuse would have blown regardless of the switch position so it's possible you inadvertently caused the fuse to blow.
Yes, and it most likely means that power is getting to the switch. Leave the Brown/Blue on and check from its terminal to ground. You should have battery voltage. If that's good then the white wires should have battery voltage when the ignition is on and the Brown/Green should when the taillight is on, and the Blue/Yellow when the headlight can be turned on.
 
You could measure the resistance thru the switch. There should be no measurable resistance with the key on.
Measuring for voltage at the output won't necessarily tell you if there is a problem with the switch. You could have full voltage but a corroded condition which means the switch cannot carry enough current to do the job, or intermittently cannot do the job.

Hope that makes sense.

Glen
 
You could measure the resistance thru the switch. There should be no measurable resistance with the key on.
Measuring for voltage at the output won't necessarily tell you if there is a problem with the switch. You could have full voltage but a corroded condition which means the switch cannot carry enough current to do the job, or intermittently cannot do the job.

The problem, however, appears to have been identified as a blown fuse so voltage wasn't reaching the ignition switch.
 
I have clear fuel lines, there is no problem with getting fuel to carbs. The present bike problem is that (a)it turn itself off while running and (b) the fuse blew. I plan to replace the fuse and have ordered a new ignition module. I still think I need to trace wires to make sure the problem is not the wiring.
 
The problem, however, appears to have been identified as a blown fuse so voltage wasn't reaching the ignition switch.
Didn't that blown fuse likely occur during testing?
I assume the intermittent running problem is still there. It doesn't sound like the ignition switch or kill switch have been tested for continuity/resistance yet.


Glen
 
I have clear fuel lines, there is no problem with getting fuel to carbs. The present bike problem is that (a)it turn itself off while running and (b) the fuse blew. I plan to replace the fuse and have ordered a new ignition module. I still think I need to trace wires to make sure the problem is not the wiring.
Ok so it instantly cuts out ...and doesn't feel like its running out of gas when it cuts out...?
Intermittent issues are the worst to diagnose.. especially if you can't force the fault.
 
Didn't that blown fuse likely occur during testing?

Yes, and could have been caused by...

Apparently pulling the fittings on and off with the ignition off blew the fuse.

...where the disconnected brown/blue terminal possibly came into contact with the headlamp shell (as it's a Mk3) or some other grounded part so it could have been the "testing" that blew the fuse as there was no problem with the lights, ignition, etc. until the fuse blew.
 
If the switches check out as OK and the wiring too, then Margie could look at the ignition itself. What type of ignition is the bike using?

Glen
 
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