Headlight Wiring Woes

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gspd
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Joined: Tue Aug 03, 2010 8:04 pm

Re: Headlight Wiring Woes

Post by gspd »

Sorry for my initial reaction.
Everything is fixable.
The problem is that your wiring has been modified, your bike no longer has it's original headlight/igntion switch assembly.
That and any other mods that we don't know of make the diagrams pretty well useless.
It's an impossible task for anyone to attempt at a distance; this is a modified setup that needs a hands on approach and a certain level of know-how and experience.

Don't give up - Do one thing at a time.
First get the ignition going, then the lights, turn signals, brake lights, charging, etc

As far as the indicator lights in the cluster;
oil (red lens) power with key on, ground through oil pressure switch
alternator (orange lens) power with key on, ground through voltage regulator/diode board
neutral light (green lens) power with key on, ground through neutral switch
high beam (blue lens) power with high beam on, always grounded
Dash illumination, 2 or 3 bulbs, power with lights on, always grounded
flasher indicator (in headlight shell) connects to hot lead from both flashers, no ground

I don't know how else I can help from afar. sorry :oops:
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
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StephenB
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Location: Ontario Canada
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Re: Headlight Wiring Woes

Post by StephenB »

A couple of years ago, I had the same problem and summarized wiring diagram and clean pics from an unmolested /5 headlight here, in that website:

http://www.stephenbottcher.net/BMW/R755 ... wiring.htm

That together with other advice shouyld get you sorted.
Some of the above is fact, some is fiction, some is my personal imagination and some is just simple truth. [me]
http://www.stephenbottcher.net
Jean
Posts: 1100
Joined: Wed Aug 18, 2010 7:43 am

Re: Headlight Wiring Woes

Post by Jean »

hudson, wires that have a basic white color are "normally" connected to headlights or something to do with the headlights, if that wire is part of the original wiring. Were there any extra lights up front?
In a DIN auto wiring, the White/Black tracer wire goes to the "dip" switch. That's the part of the switch that lets you flash the headlight when you want to pass or otherwise signal someone you are overtaking. On my /5, it's activated by pressing the left-hand switch lever (handlebar) downward. (UP is for high-beam ON.) it will flash the high-bean whether the headlight is on or not.
Clemson, SC
R100s, R75/5
hudson
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Joined: Tue Sep 14, 2010 5:08 pm

Re: Headlight Wiring Woes

Post by hudson »

No problem. Wires look like well, a mass knot of wires! Never looks clean no matter how neat I am being! :D Thanks for the reminder on the bulb colors. Now I just need to tell them apart from the wiring! :o I didn't know that wasn't the original ignition switch, but I can see mine is clearly different.

Stephen - will study your information. I am sure it will help.

Jean, little confused about the white/black wire from the main harness. I double checked. it is not from the hi-beam switch on the handlebar. not sure how that hooks up to it.

Thanks again. Will keep plugging a long...
hudson
Posts: 173
Joined: Tue Sep 14, 2010 5:08 pm

Re: Headlight Wiring Woes

Post by hudson »

BTW, found out that the ignition switch upgrade kit was from Rocky Point Cycle. Bill was kind enough to forward me the kit directions, so this will help out too! I'm getting there... :)
Jean
Posts: 1100
Joined: Wed Aug 18, 2010 7:43 am

Re: Headlight Wiring Woes

Post by Jean »

It is very difficult to trace wiring after mods have been made that do not follow the original DIN wiring color code.
With the ignition-mod-directions, you need to draw your own schematic and somehow make copies (to write on while you do your work!)
Best 'o luck...this is sure a can of worms!!
Clemson, SC
R100s, R75/5
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Ken in Oklahoma
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Joined: Tue Aug 03, 2010 5:10 pm

Re: Headlight Wiring Woes

Post by Ken in Oklahoma »

I'm thinking that the best thing to do is to buy that new wiring harness and install it. The non standard ignition switch would be a minor thing and wouldn't represent much of a glitch in future troubleshooting.



Ken
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There's no such thing as too many airheads
hudson
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Re: Headlight Wiring Woes

Post by hudson »

Ken in Oklahoma-

I did buy and install the new main wiring harness, starter/turn signal switch harness & high beam/horn switch harness. Everything has been wired up. I have power to my headlight and hi-beam only at this time. I wired up everything like the diagrams & color codes fairly easily.

The different/updated ignition switch has a wire that supplies power to the 8-wire connecting block that came with the kit. In the directions, it was recommended to piggy back the oil, charge and nuetral indicator bulbs as the previous owner did from a terminal in the connecting block. There is a tale piece that comes out the last bulb and is suppose to connect to another wire (to supply power to the starter/turn signals would be my guess). The PO had this spliced onto another wire via a wire tie cap (not recommended). I believe it was a green wire that came out of the either starter turn signal harness or the front brake switch harness. Not sure how to get the power to these yet.

Jean -

That white-black wire runs from the front to the end of the main harness to the tail light, so I assume it supplies power to these lights.
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Ken in Oklahoma
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Re: Headlight Wiring Woes

Post by Ken in Oklahoma »

hudson wrote:I did buy and install the new main wiring harness, starter/turn signal switch harness & high beam/horn switch harness. Everything has been wired up. I have power to my headlight and hi-beam only at this time. I wired up everything like the diagrams & color codes fairly easily.

The different/updated ignition switch has a wire that supplies power to the 8-wire connecting block that came with the kit. In the directions, it was recommended to piggy back the oil, charge and nuetral indicator bulbs as the previous owner did from a terminal in the connecting block. There is a tale piece that comes out the last bulb and is suppose to connect to another wire (to supply power to the starter/turn signals would be my guess). The PO had this spliced onto another wire via a wire tie cap (not recommended). I believe it was a green wire that came out of the either starter turn signal harness or the front brake switch harness. Not sure how to get the power to these yet.
Hudson, you're the man on the scene and you have a plan, so I'm not inclined to second guess you. Now, having said that, I will give you the benefit(?) of my thought processes.

Except for the ignition switch, which is unique, I take it that the rest of the electricals are as BMW set them up. The ignition switch is complicating things for you though, it appears. However you're keeping that 8 wire connecting block, which means a significant departure from the BMW design. And it appears that the wiring block requires significantly more alterations to the stock wiring, at least inside the headlight shell.

I would be inclined to ditch the wiring block along with the "custom" wiring that it apparently demands. I may be on shaky ground here because I'm unfamiliar with /5 ignition switch. But here goes anyhow. I would expect an aftermarket ignition switch to have 4 or 5 functions: Accessory On, Ignition Off, Parking Lights On, Ignition On, and perhaps turn-the-key-to-start, not necessarily in that order. I would expect the /5 stock Ignition switch to have the same functions, minus one or two or three (specifically Accessory On and/or Parking lights ON functions and perhaps Start). If you can figure out the switching logic of the aftermarket switch then you should be able to wire it up like the stock switch. If you do this then you won't have the 8 wire connecting block to confuse the issue. You may have to come up with some 2 in 1 adapters to wire up the aftermarket switch, but the benefit would be that your bikes wiring would be pretty damn near stock.

This will benefit you later on when you can't recall exactly how you wired up the switch and related stuff.

Just a thought.


Ken
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There's no such thing as too many airheads
Jean
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Joined: Wed Aug 18, 2010 7:43 am

Re: Headlight Wiring Woes

Post by Jean »

According to my DIN/BMW schematic (old!), tail light wire is Green with Black tracer. Stop light is Green with RED tracer.
Just thought you'd like to know.
Doesn't make you feel any better tho, does it?
Clemson, SC
R100s, R75/5
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