No Lights

CALfeRacer

Fat man on a little bike
So, I have run to the point of having no idea where to go as far as the electronics on my 93 Nighthawk 250.
When I bought the bike, the lights didn't work and the PO said it was a bad battery. So, I got the battery load tested- it was OK. Next I checked and cleaned the grounds and the battery cables/terminals. Still nothing. Replaced the starter solenoid, nothing. Checked the ignition, got infinite resistance when off and just over 0 when in on. So that should be good. Got a new (07) wiring harness, and still nothing. All the fuses look good. The bike bump starts easily, and runs great. Problem is, I have no head or tail light, blinkers, horn, starter, nothing. Bike will run with the ignition in on or off, even with no key. Kill switch works (only way to stop it! ;D).
So, here is where I come asking for help. I am totally out of ideas of what it could be, does anyone have a clue?? I've looked over the wiring diagram and am not sure where to look from here.
Thanks!
 
I would check that all of the switches are wired properly, it kinda sounds like the PO posibly disconnected everything and was too lazy to wire it back up. If theyre wired correctly check that they're functioning.

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I know they're all wired up, I spent some time plugging it all back together earlier today haha.
I'll check the switches when I can get my hands on a multimeter, hopefully sometime tomorrow and if not then on wednesday for sure. Would bad switches cause there to be no lights?
 
Yes the power goes through the switches to get from the battery to the lights. Im sure someone with more knowledge than me will chime in at some point.

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Just an update, I checked all of the switches and they are working. Checked the fuses and they are good as well. Re-checked battery cables and grounds. Any ideas?
 
Something isnt wired correctly if the bike will run with the ignition switch off. And the lights are wired through the ignition switch.
I'd start there when checking if its plugged in/wired properly ;)
 
It looks to be plugged in correct, based on the connectors and the wiring diagram. Could it be that the switch is worn out and allowing a connection to occur even when in off? I'm just confused though because when I tested it with the multimeter, it all looked ok.
 
Anything is possible. But usually when thet go bad, you lose connection, not gain it. Do you have a wiring diagram for the bike?
 
If it is running regardless of whether or not the ignition switch is active, you may have bypassed it entirely - and my guess would be that the lighting circuit draws power from (or is on a relay activated by the) ignition switch. I think you'll find that correcting the ignition problem will lead to your lighting problem being solved as well.
 
I do have a diagram, I can scan and upload it if that helps.
Looks like you're right on the lighting circuit. When the switch is on, it connects a black and red wire. the red goes to the solenoid & min fuse, the black goes to the fuses for head and tail lights, which are also branched to the indicator lights, and power to the controls. So, is the next step to replace the ignition with a new unit? I'm perplexed because the ignition switch tested fine on the multimeter. Maybe because of the damaged housing it is making contact or allowing wires to contact, shorting it out?
 
CALfeRacer said:
So, is the next step to replace the ignition with a new unit?

Next step is to figure out what's wrong. Do I understand correctly that you can start the bike when the key is in the off position?
 
Rich Ard said:
Next step is to figure out what's wrong. Do I understand correctly that you can start the bike when the key is in the off position?
Yessir. Start, ride, the whole lot. Just no lights.
 
You should not have power to the coils without the ignition switch on. My guess is that somehow you have wired it incorrectly, such that you have a hot lead connected directly to the killswitch rather than to the ignition switch (which would then in turn power the ignition and lighting circuits.)
 
Alright, I'll check when it stops raining out. Should be easy, only two possible wires I could have accidentally swapped. Other than those two, one of which goes to the ignition and the other to the kill switch, all of the connectors are color coded, or only have one option to plug in to as far as a male/female counterpart on the harness. Pretty idiot proof. But, if those two wires got mixed up that would explain it. If that's not it, what should I be looking for?
 
Find the wire that's providing 12V to the killswitch and trace it back. Figure out where it deviates from the wiring diagram.
 
More importantly - as you go through the harness, make sure everything that you see matches up to the diagram. We just wrapped up a Bultaco (which has a bizarre wiring harness) that has been giving us fits for more than a year - and discovered that the root of all the problems we've been having were that (a) a frame ground had been powdercoated over, and (b) two wires had been very carefully reversed within the stock harness, and done such that it wasn't obvious without comparing every wire, one by one, to the factory diagram.
 
Ahhh darn. I was hoping that by getting a new harness I wouldn't have to open it up... oh well. Hopefully the error is just me not plugging something in right (hell, probably wouldn't be the first time) and not a bad harness.
Just a thought, I know this bike has been dropped, could that somehow have messed up the starter motor ground? And would the symptoms match up with a lack of starter ground?
 
Nope. The starter grounds through the case where it is attached to the motor - and even if it weren't grounded, it wouldn't give you the result that you're seeing.
 
Alright, that's what I thought. Well, once it stops raining I'll head out and check the wiring. I need to get off campus so I can have a shop already...
 
So, I believe it is the ignition switch. With the switch off, the bike will not start. with the switch hooked up, it will. I checked the wires coming off the switch and they are all visually in good shape. I believe there must be a short somewhere inside of the switch, causing it to give power when off. I cleaned the inside metal surfaces, but I noticed the contact balls are all pretty worn down. I think this could be causing the metal plate the balls sit on to sit close to the contact points, which could be making a short. I'll be checking with the local moto shop to see if they have any universal ignitions.
 
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