Headlight wont work, '85 vt500c

[johnny_i]

So as i was tearing down my bike and trying to get rid of some things i decided i would start cutting some wires that i didn't think i would need, real smart i know. got rid of the wires that go to the front turn signals as well as one of the horns. I thought i was only cutting wires that wouldnt affect anything else but now im not sure. when i went to plug everything back in today the headlight wasnt turning on. I looked back at the wiring diagram a few times but then gave up for the day. Im going to try again to figure out what my genius self did in the next few days. Just wanted to ask if anyone has a recommendation of something i should look at right away or places where it might be causing the problem? Thanks in advance for any help.

[jkennatx]

So, I had an electrical issue on my bike the other day, and I can tell you what worked for me. I was looking at the clymer manual wiring diagram, when I suddenly remembered I spent 9 years in the Marine Corps trained in communications electronics, and went back to that mindset. So all I can give you is good troubleshooting advice that has worked for me.

1. Get out your schematic, and a full set of colored map pencils.

2. Trace all the wires on the diagram and make a color coded legend.

3. When you trace the wire, pay attention to what it is connected two. You will begin to see a pattern.

4. As you color code it, make note of what signal is being passed down the wire, note it in your legend. Think, "Left Turn Signal Control", "High Beam Control", etc...

5. When it is finished coding, look at how all the switches/diodes work. Trace the signal, thinking "This switch conncts this and that", "or, "this diode keeps voltages seperated", etc...

6. Get out your multimeter and test the circuit about in the middle, for example, at a switch.

7. If the signal is good there, for example, the switch's resistance is correct, as in it opens and shorts properly, look after the switch, if it is bad there, trace it back.

8. Remember to check obvious and easy things first, but bear in mind tracing the signal will work every time.

9. You could probably troubleshoot any electrical problem on the bike in about 15 minutes this way.

10.....I'm assuming you have a shop manual and a good schematic.

[Moparsrule]

The first thing you should do is check the fuse, then get a meter and check for power at the headlight, you might have cut the power wire without knowing it.

[oconeedan]

Check the fuses first. But your initial post makes you look, as you said, unsmart.
Getting rid of turn signals, cutting unwanted wires...I see no good in either.
Dan

[johnny_i]

Thanks guys, going to try and find out the problem today.

[superdiver]

WOW, cutting wires without know where or why... lol

OK, we have all done stupid things (and this was very stupid), and I am SURE I will do more stupid things as my wife has not found a cure for me yet... so take it as a learning experience...lol

Bout how many wires do you remember cutting? When i redid the wiring on my 84 700 a few weeks ago i was delightfully surprised at how color coded this bike was and how simple it was. That might give you MUCH NEEDED hope! If you are "sure" you got them back together correctly (wake up from your dream first) and if the light doesnt work I would bet you blew a fuse by one of the lose ends shorting out or something...

If you didnt cut a TON of wires it shouldnt be too hard to figure out...

[johnny_i]

So i tried to do some problem finding today to find the source of the problem but can up empty handed. Maybe I should have explained what I did a little better. I cut the wires that connect the dash in. Has the indicator lights for neutral, turn signals, temp. Etc. I'm not going to be putting it back on the bike so I figured cut it out. This is now where I'm guessing the problem arose. The thing that I'm confused with is every time i check the diagram to my knowledge this should not affect the headlight, my knowledge us very limited when it comes to electrical though.

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[johnny_i]

After taking a break today I went back and looked at it one more time and got it! I feel like such an idiot, made such a huge fuss and spent so much time over nothing. IT WASN'T GROUNDED. Can't believe I hadn't checked that. Thank you guys for all of the suggestions, at least I got to know pretty much every wire that's on my bike haha.

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[jkennatx]

Good deal.


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[superdiver]

so you are removing the lighted dash board thingy? The one with the turn indicator blinkers, the neutral light and the fuel light on it?