brake light wiring - removed idiot lights

rattpunk

Been Around the Block
To start the bike is a 82 cm450c.

So, I was trimming down some of the big ugly off the bike and everything was going fine. I took off the signals all around, the tach, the idiot lights and the entire rear light assembly which I replaced with a cats eye. What has me stuck is the brown wire for the new break light. What I can figure from the diagrams on Google images and my Clymers, it looks like the brown break wire eventually goes through the neutral indicator light and back out somewhere. Btu where...? My thought process is to see where the break light went into on the assembly, trace where it would have come out of that assembly and then plug it into that...


I guess my question for you all is two parts:
Am I looking at this problem the right way?
How have you dealt with this?


If it'll help you help me, I can post up some pics. I'd like to get this thing inspected this weekend so I can venture out and not worry about loosing the bike over a single wire.


Thanks,
Tyler
 
The brown wire is your running light and should go to ignition power or if you have a headlight light on/off switch to that switched power.

The brown should share the same power source as your idiot lights (but completing ground on the light green neutral indicator wire illuminates the light).

The green wire with yellow stripe runs from your brake switch and is your brake light wire. The green solid is ground.

Can you post up a pic of the part of the wiring diagram you're working off of to be sure? I'm going of 70's 360 wiring...and memory...
 
eram said:
The brown wire is your running light and should go to ignition power or if you have a headlight light on/off switch to that switched power.

The brown should share the same power source as your idiot lights (but completing ground on the light green neutral indicator wire illuminates the light).

The green wire with yellow stripe runs from your brake switch and is your brake light wire. The green solid is ground.

Can you post up a pic of the part of the wiring diagram you're working off of to be sure? I'm going of 70's 360 wiring...and memory...

All the above is correct. Are you confusing the Brown with the white tracer? Thats the wire that supplies power to the gauges and idiot lights.
 
Thanks guys.

I think you pointed out the first problem. Looking thru the schematic again the brown appears to go to the ignition (not sure where it goes from there, speedo?). And the green/white(yellow?) looks to be the break. Second thing I might have gotten mixed up on is the wires from the new unit. I had the black and yellow confused, without testing the unit I assumed the black was ground, not the yellow.


pics:
Wiring diagram from correct Clymers
Honda-CM450C-Electrical-Wiring-Diagram.jpg



Wires from new light (not my image - found on a forum post elsewhere regarding similar issue - but same light and same stock bike wires)
Emgo_CB900c.jpg



Inside bucket - bit of a mess...
2012-06-30_13-41-36_580.jpg

2012-06-30_13-42-38_958.jpg


Original light wires:
2012-06-30_13-40-59_168.jpg



After I replace a fuse, and double check the connections from new light to stock harness wires, should I try just plugging the brown/white into that brown???
 
I have that same light. It is goofy how they colored the wires. IIRC, Black goes to brown, Red goes to Green/Yellow, and Yellow Goes to ground or Green on the stock harness. Your stock Brown wire comes from the key so no need to plug it into Brown/White.
 
Great.

Thanks again. I was really thrown by the brown just hanging out in the headlight bucket all alone like that (figured it must have been an incomplete circuit), and with the confusion over wire colors... anyway. I'm out of town all night but will revisit in the AM and post up results.

Tyler
 
I haven't broken out the manual yet, but thought I'd update with what I know...


I have the yellow to the green and tried both combinations of black and red to green/white and brown. Just to see what would happen. Well either way I tried it both of the filaments stayed lit. I guess that may point to the switch being out, but it worked fine on the previous light. I checked around in the headlight bucket again and don't see any loose wires other than what was mentioned before (blues and oranges for directionals and the brown & brown/white that were said to be from the key and to the gauge lights).


I've got a book I never read through on motorcycle electrical troubleshooting and a Clymers to go through now, but please help.


Why in the hell would the break light stay lit..? ??? maybe one of the switches is stuck open...


hhhmmmmm - I'm gonna check those switches again now before busting out the books.


Thanks for checking in.
 
Youve pulled the signal lights and idiot lights already, why not just make your own harness. get a spool of wire and a soldering iron, some connectors. Its intimidating at first but you'll have it done in an afternoon. Oh a testing light is a must.
 
Do you maybe have the wires flip at the brake switch? Sounds like you have continuos power going to the green/yellow.
 
Ok, your dilemma is very familiar. I had similar problems so I went and rechecked mine. I recall I had lots of problems with the yellow ground wire. I ended up removing it and running a wire from one of the screws on the fixture. See attached photo.
320440cb-d364-861c.jpg



Sent from my iPad using Tapatalk, bitches.
 
Ok, I'll see how that works. So the light is still getting grounded by that screw?




I have been thinking about making a new one or stripping an aftermarket replacement, but until I can commit the time, I'd like to keep the bike wired and get it legal.
 
djelliott said:
I have that same light. It is goofy how they colored the wires. IIRC, Black goes to brown, Red goes to Green/Yellow, and Yellow Goes to ground or Green on the stock harness. Your stock Brown wire comes from the key so no need to plug it into Brown/White.

Interesting. I have the same or very similar cats eye tail light on my 76 KZ400 and it wired up about how you would expect. Red wire from the light went to the red wire from the harness, which is ignition/on/power. Black wire from the light went to black & yellow wire in harness, which is ground on a Kawi. The yellow wire from the light went to blue from the harness, which runs to the brake switch.
 
Hmmm.. maybe they had the Kawi harness in mind when picking wire colors... way off for a Honda ???
 
Going to tackle this again tonight. Played around with the yellow ground as posted above. No dice.


Correct me if I'm wrong, the filament stays on because either the switches are not working or the wires are touching, right? I mean, the way it seems to work to me is that the break light gets no power to the filament unless you activate either of the two switches... I've unplugged the front switch from the control, still lit. I haven't gotten to the back one yet, but if I unplug both switches and the light stays on that must(?) mean there are wires touching somewhere?


The purpose of the ground is to complete the circuit right? so if I unplug that, the light shouldn't light at all.


I'm going to try to test all those thoughts when I get home, but if I'm just all wrong about this go ahead and school me.
 
Hook up the green-yellow wire to the light, and hook up the ground wire (solid green), but leave the brown disconnected. Then disconnect the front and rear switch wires (don't leave the wires attached and take the front switch off, because when the button pops out it's completing the circuit)...You should *not* have illumination at that point. Then hook up the front switch, test. Then the back switch, test.

If your rear brake switch is connected but isn't adjusted correctly (like if the spring is pulling on the switch without depressing the pedal) it'll keep the light on...

If you do have illumination with the switch wires removed, you're right - there's a short to constant power (e.g., brown but not the only possibility) somewhere.
 
Yeah, so with both switches removed and the wires left disconnected, brown unplugged, still power to the break light. Its just down to inspection for a short at this point.

Think ill start in the headlight bucket with all the leftover wires from removed components.
wish me luck.
 
Make sure to check your grounds too. Bad grounds can do wonky things like make things light up when they shouldn't.
 
I didn't consider the grounds being a possibility. There were a couple in the headlight bucket that I'm not entirely sure went back to where they were supposed to. They were in those 4-way connectors, two set of em. So could that be it? Everywhere else I looked everything was Jake. I guess I might as well swap them around and see if there's a difference.


Oh, and another bit of information. The new battery was dead after sitting for a few days. So that also suggests to me some kind of short. Could that also be due to improper grounds in the bucket.
 
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