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Discussion Starter · #1 ·
So was supposed to finish this project this weekend, all wiring redone new parts all around and everything is working except for the rear brake light is staying on...ughh

So there is multiple issues here for tracking this down... one, as I have mentioned many times before... I dont know $#!+ about electrical... all the wiring I just took pictures of connections before removal and then attempted line everything back up... yes I have a ducati Haynes manual... this wiring diagram to me makes me question my intelligence significantly... it just looks like everything is connected...lol

On top of redoing the wiring, all the levers (front and back) are new and the controls up front are new. Also most of the wiring is not stock, and I have integrated LEDs in the rear as my only light (outside of an HID kit for the front plowsand high beams) So there (to me) seems to be an overwhelming amount of possible issues and I am just trying to get the list down if I can.

Have the whole bike back together and am also just a bit upset that I didnt test the brake lights before putting it all back together.

I have rechecked all the connections, checked fuses, removed levers and pushed the pins back and forth to make sure they were not stuck. Also just pulled the front level off completely as well is unplugged the rear break wiring and still the light did not go off.

From the brake light I have 2 lines that I belive go to the integrated turn signals (which work perfect) and then a run of a separate 3 lines. If I unplug one of them the light goes from bright back to the dim running light, if I unplug another the whole light turns off, if i unplug the 3 nothing appears to happen.

Any help is appreciated.
 

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The rear brake light switch sounds like the culprit here. A cheap multimeter that beeps on a continuity test. Unplug and probe the two wires from the switch and push the in in and out. The metre should beep every time it’s pushed in. An extra set on hands work well here.
 

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Do you have the light wired correctly and didn't wire the brake light cable to the rear light bulb and the rear light cable to the brake bulb? If so, it would look like the brake light was on every time you turned the key.
 

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2001 900SSie
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IMO the wiring from the harness connector to the connector for the Brake/Tail is not correctly wired.
Particularly if you have both. brake switches disconnected and the brake light stays on.
To me this indicates that the power for the tail light is connected to the brake light.

Do you have a multimeter (MM)?

If so, with the bike off set the MM on the lowest resistance scale.
Unplug the connector.
Connect one probe, does not matter which to battery negative.
Then with the other probe try each of the pins to find zero resistance, the others will be infinite.
Now you have identified the common negative. I expect that this will be the wire, that when you disconnect it, makes all lights go off.

With all brake switches connected.
Now change the MM to the 20 Vdc scale.
Put the black probe into the connection identified as common negative.
Turn the bike on.
With the red probe check the voltage one at a time for the other two wires.
One should be 12V or more - this is the permanent tail light power.
The other should be zero until you pull or press a brake lever and it will be 12V or more.

Next look at the wiring instructions that came with the integrated tail light.
Then make sure the wires identified above are connected to the correct pins in the connector.
What colours are the wires in the integrated tail light for brake, tail and negative?
 

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Discussion Starter · #6 ·
Okay got it down by trial and error to the front end.

I unplugged the wires comming out if the right front brake lever and the light return to running light and pressing on the rear brake lit it up correctly.

So with that said, where could my issues be at in the front?

Again, running new levers as well which have never been tested before this.
 

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Discussion Starter · #7 ·
Sorry I was mid typing that post while tinkering so I didnt realize three comments came in in the last 10 minutes so I will read and update
 

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Discussion Starter · #8 ·
@xracer, thank you but now I think I have confirmed it's a front end issue
@Sherpa23F, no I have no idea if I wired anything on this bike correctly...lol
Yes brake light would come on if the bike was turned on, now with the front disconnected at the front control is returns to normal running light
@belter, sorry what I meant was if I unplugged one of the three lines comming into the rear light it stayed lit. It appears the one I unplugged was the rear brake, so unplugging it did nothing because it was the front brake turning it on.
@Punch I think with the updated find that it's a front issue, it may be something different then what you wrote but let me know if that is still valid and I will check.

Really appreciate the help so far.
 

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what year is it? does it have the front switch with the little plastic cylinder between lever and switch? does the replacement lever contact the switch correctly?
 

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Discussion Starter · #10 ·
what year is it? does it have the front switch with the little plastic cylinder between lever and switch? does the replacement lever contact the switch correctly?
It's an early 95 (p8)
After market lever, no idea how to determine correctly or not. I just know even with the lever removed the light was still on

I will tinker again with it and update
 

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Discussion Starter · #11 ·
This is the type of lever that has a (copper?) Pin that slides into the rubber covered brake actuator (similar to how the rear works) the front lever is then adjusted so that when released it breaks compression of the pin and should theoretically turn the light off. However with the pin compressed or decompressed (or even completely out, the light stays on as long as I have it plugged in.
 

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Discussion Starter · #12 ·
Heres the level pulled off and the pin I'm talking about, I have no other plastic part that I am aware of... (or lost it due to working in the dark)
 

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@xracer, thank you but now I think I have confirmed it's a front end issue
@Sherpa23F, no I have no idea if I wired anything on this bike correctly...lol
Yes brake light would come on if the bike was turned on, now with the front disconnected at the front control is returns to normal running light
@belter, sorry what I meant was if I unplugged one of the three lines comming into the rear light it stayed lit. It appears the one I unplugged was the rear brake, so unplugging it did nothing because it was the front brake turning it on.
@Punch I think with the updated find that it's a front issue, it may be something different then what you wrote but let me know if that is still valid and I will check.

Really appreciate the help so far.
More and better info.
No need to do what I suggested as you have now isolated it to the front switch.
As Belter wrote about the little switch.
This will be a microswitch of some sort and may be stuffed, clogged so that it does not open.
Worth investigating its operation.
 

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Heres the level pulled off and the pin I'm talking about, I have no other plastic part that I am aware of... (or lost it due to working in the dark)
have you removed the switch in that photo?

where the switch goes on, there is a hole in the master body that a plastic barrel sits in that is then between the lever and the switch. that transfers the movement between the two.

you're talking about the pushrod that moves the master piston.
 

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Discussion Starter · #15 ·
Heres the level pulled off and the pin I'm talking about, I have no other plastic part that I am aware of... (or lost it due to working in the dark)
have you removed the switch in that photo?

where the switch goes on, there is a hole in the master body that a plastic barrel sits in that is then between the lever and the switch. that transfers the movement between the two.

you're talking about the pushrod that moves the master piston.
Well, you found the issue my friend.
Took off the wire that connects to the level held in place by two of the smallest screws I have ever seen on a motorcycle, saw the little switch on the end and pressed it... it turn off immediately. Looked inside the lever to see what should be pushing it, and nothing is there.

I assume that's where a little plastic part goes that is presumably somewhere on my garage floor?
 

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i've got heaps of them at work. comes with a new switch if you buy oem or brembo. otherwise make one from something. i don't think a ball would work because it's longer than its diameter? maybe if you push the switch in further.
 

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Discussion Starter · #18 ·
i've got heaps of them at work. comes with a new switch if you buy oem or brembo. otherwise make one from something. i don't think a ball would work because it's longer than its diameter? maybe if you push the switch in further.
Great I got small metal dowels that should work that I can trim down for now until I can get OEM ordered in.

Really truely appreciate your help here!
 

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It's a little white plastic ball bearing thing or a plastic puck of very specific thickness and diameter as it needs to slide easily with very little movement, only a couple mm.

Shows it on the parts fiche but does not mark it with a part number.
 

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Discussion Starter · #20 ·
It's a little white plastic ball bearing thing or a plastic puck of very specific thickness and diameter as it needs to slide easily with very little movement, only a couple mm.

Shows it on the parts fiche but does not mark it with a part number.
Thank you, turns out an M8 SS bolt dremmeled down works perfect.
 
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