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Discussion Starter #1
Put on new brakes, refilled both ABS chambers, replaced 6 position aux fuse block with a 12 position (both Blue Sea, equivalent other than number of terminals), and tapped into the red/yellow wire at position 9 of the alarm unit to add an additional LED indicator.

Now, the brake lamps work fine... the first time. They stay on, with the exception of the center tail lamp, which I modded years ago to work as an extra brake lamp as well as running lamp.

My EHCS will not work once I have used the brakes. If I have not yet engaged the brakes, the EHCS works fine.

If I shut the bike down and restart, the pattern repeats and the brake lamps work, the EHCS works... until after the first engagement of the brakes.

If I tap the starter and engage the load-shed relay, the bike also "resets" as if I had turned it off and restarted it.

I think I can safely rule out the brake switches as either one causes the center brake lamp to illuminate, and it goes off when the lever/pedal is released.

I think I can rule out the auxiliary LED as it functions normally, working in synch with the indicator on the instrument panel.

HELP!!! (please... pretty please)
 

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Does the problem persist with the additional LED disconnected?
 

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you have somehow added either a high resistance ground or low voltage connection somewhere in the work recently done - have you tried disconnecting the led and see if problem still there - electrical systems with floating grounds (no common frame ground) are fun to work on
 

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Discussion Starter #4
I do not believe that I have.

Works same with/without the extra LED.

Works same with/without aux fuse block connected
 

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deputy5211 said:
Now, the brake lamps work fine... the first time. They stay on, with the exception of the center tail lamp, which I modded years ago to work as an extra brake lamp as well as running lamp.
Does that mean you release the brake lever and the brake lamps stay lit? except for the added center lamp.

Is there a relay to the brake lamps? Sounds like it is hanging up for some reason, either the contact within or for some reason, there is a sneak circuit that is making it behave like a latching relay (the output power is running back to the control input). The condition exists until the power is removed.
 

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Discussion Starter #6
Dave:

Yes

Seems like it, but unaware of a relay, and why would it keep all brake lamps energized except the center one?
 

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2005 K1200LT
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deputy5211 said:
Seems like it, but unaware of a relay, and why would it keep all brake lamps energized except the center one?
That is where your problem lies. If you wired this one to be a dual element brake light then the fault is in that wiring. Could also be a burned out element in that one bulb and it is causing some sort of feed back. Try it with that bulb removed.
 

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Sounds like you have a feedback into a relay which is energized by the brake lamps. In other words, the downstream load on the relay is feeding back into the control circuit when you energize the brakes. Check everything on the brake lamp circuit which is fed by or connected to a relay.
 

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deanwoolsey said:
Sounds like you have a feedback into a relay which is energized by the brake lamps. In other words, the downstream load on the relay is feeding back into the control circuit when you energize the brakes. Check everything on the brake lamp circuit which is fed by or connected to a relay.
Sounds to me that you have inadvertently made a latching relay. Once it is energized it is self feeding, meaning that it feeds the control portion of the relay from the load side.

Robert
 

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Discussion Starter #10
I will check the bulbs and wiring again later tonight when I get home.

The tail:brake bulbs all work in both single and dual filament mode, and this configuration has been working fine for years as is. Is confusing to me why only the centre bulb maintains its functionality... IIRC it is simply tapped off the other brake lamp socket, at least for brake lamp functionality.

Truth is often stranger than fiction. :-D
 

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The Clymer manual shows a brake light relay that is actuated by the two brake switches. Sure sounds like you are latching it. The EHCS diagram shows an input from the same relay going into the control box for the stand (it's function is not immediately obvious, but it is probably an interlock of some kind). This adds weight to the latching issue.
 

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The most perplexing thing is that it has worked fine for years until recently. But that points to the work you just did. There must be something there that is causing this. Can you try isolating the fuse block and anything else electrical you recently changed?

All else fails, look at what you messed with last.
 

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r_figueroa said:
The Clymer manual shows a brake light relay that is actuated by the two brake switches. Sure sounds like you are latching it. The EHCS diagram shows an input from the same relay going into the control box for the stand (it's function is not immediately obvious, but it is probably an interlock of some kind). This adds weight to the latching issue.
Clymer is wrong on that item as the the two switches only talk to the ABS unit and the ABS unit, in turn, drives the brake light relay. This applies to all LTs with the integral brakes.
 

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Discussion Starter #16
deanwoolsey said:
So when you apply the brakes, all three lamps light and then the outer two stay on after the brakes are released?
Yes sir.
 

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Discussion Starter #17
deanwoolsey said:
I suspect your latching relay issue is directly related to the added LED. I would disconnect it and see what happens.
I did, and no change. The LED taps into the LED lead coming from the alarm box and goes to battery ground.

I just got home from my P/T job. Will have to look at it tomorrow as I have to cram tonight and tomorrow for my pharmacy exam tomorrow afternoon.
 

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Discussion Starter #18
dukey33 said:
The most perplexing thing is that it has worked fine for years until recently. But that points to the work you just did. There must be something there that is causing this. Can you try isolating the fuse block and anything else electrical you recently changed?

All else fails, look at what you messed with last.
That is my plan. I did it before but in a hurry. I am going to d/c the fuse block and the LED, and then test. I will then add back circuits on block one at a time, testing after each add. Maybe in my zeal to connect everything before dusk turned to night, I may have misconnected one of the accessories to the block.

I can only hope that it is that simple. :D
 

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I too added the center bulb as a stop lamp. I just tapped into the hot feed for the two outer lamps. It is very odd that the two outer bulbs stay lit and the center bulb goes out. I suspect an issue with some type of aftermarket brake lamp flasher or extra brake lamp circuit. Try pulling the lense assembly and checking around behind it for an added relay or flasher unit. It's only held on by those two funny looking bolts at the rear interior of the side cases.
 

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Discussion Starter #20
NOT the center bulb.

NOT the additional LED.

NOT the circuits on the replacement aux fuse block.

[HUMBLE MODE ON :eek: ]
As suspected, in my zeal to do "one more thing" between dusk and dark, I swapped out the six-place BlueSea fuse block with a 12-place that I have had sitting around for some months. I inadvertently reversed the wires bringing power to the fuse block, battery ground to where the positive should have been and vice-versa. No doubt this introduced a ground fault into the vehicles systems that was ignored by almost everything. As in many things in life, almost was not quite enough. :rolleyes:

Now, every wire or pair going in and out of the block is tagged with a tag indicating what it is. Wires had cabling stickers on them before, pre-numbered tape wrapped around each lead. Over the years, some of these came undone or their counterpart on the fuse block failed. Now they are marked with zip ties with tags on them, clearly labelled with in/out and to/from where.
[RETURN TO NORMAL MODE]

Thanks to all for the input. Since it was working fine for years, I pretty much knew it was a recent change. Disconnecting the fuse block did not work, but probably because I did not isolate both feeds to it.

Lesson re-learned: Fast is slow and slow is fast. Doh!

Now I can get back to studying with a clear head. Leave for the exam in three hours and site in just under four.
 
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