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Discussion Starter · #1 ·
Just replaced my battery after a cold winter's sleep up here and a dead battery. I know I hooked up Positive first, then the negative. Saw a spark and though it odd. but now think it was the 15amp fuse blowing noise I heard for the Brake, Horn, Alarm & elec case locks. Now ckecking it with ignition off it shows 12.92V DC across it, same as battrery. I understand there are some relays under the gas tank and I traced them down and replaced the two relays with the correct wires running into them and that did nothing, still blowing fuses. A red one for the positive side going to a middle yellow relay and a red/white band wire going to the middle black relay Are there also some relays under the front headlight fairing does anyone know? I have my old harness that got smoked in 2010 and see that there are two Gray relays that look like they were in that area possibly. Are they maybe for the horn? The bike started right up and I rode it over 300 miles not knowing the brake lite didn't work. I noticed something when I hit the horn button and no noise came out. That got me looking. Anyone had a similar problem? Any ideas? WE just had our first really warm day up here and I spent it removing tupperware and fuel tank to get to the electric box. Anyone have a schematic of the entire electric system can't find one anywhere in the online manual I have. Bike is an 05 LT. The taillights are working as are everything else on the bike. Runs fine too. Getting 46 mpg too! Just the stupid short I can't seem to pin down. Any help will be appreciated. Thanks
 

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if you unplug the suspect relays and replace fuse does it still blow, before or after relay, gray relays in front are probably for windshield
 

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Wrencher Extraordinaire
2005 K1200LT
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The electronics (not the actuator) for the EHCS is also fed from this fuse F12. The spark on battery connect is normal.
 

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Discussion Starter · #4 ·
I undid all the relays like you asked and it still blows the fuse. With even every relay out it blows the fuse without the ignition even being turned on. If someone with a multimeter out there is brave enough they could test across the fuse leads(15amp left box 2nd one down on left side, with their bike off, Red lead to right (inside) and black to outside leg of fuse(red/white wire) and see if they have voltage that might narrow the field for me. I sort of figure its hot all the time even with the ignition off and even in the locked position where nothing is on. It's the same circuit as the alarm and that would have to be on at all times to work. Also if with your ignition off, check if the brake light comes on with ieverything off. Might need 2 people for that one. Good things to know anyway. The gray ones ARE for the windshield! Thanks on that It clicked in after a short period of sleep. This is one for the books! Thanks for the help guys. We lost the BMW dealer here in Idaho (Beaudry) a while back and someone has taken it over in Spokane but they aren't that familiar with LT's mostly the newer stuff.
 

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2005 K1200LT
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I looked again and there is a conflict on the ECHS electronics. The main diagram shows it is fed but fuse F12 but the actual diagram for the ECHS does not show it.

All you have on that circuit is the brake light relay, horn relay and alarm. I checked mine and if you pull the fuse and measure from the top pin to ground you get 12v (battery voltage) all the time.

Next set your eter to ohms and measure from the bottom terminal to ground. You should see greater than 1 meg ohm. I suspect your reading will be much less. You may have to start tracing wires to see where the short is. At least you can use the ohms reading to test instead of more fuses.:)
 

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jzeiler said:
At least you can use the ohms reading to test instead of more fuses.:)
There is that "mean" streak starting to peek its head out, John! ;)
 

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2005 K1200LT
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Yes it can. You can even bypass it altogether. Just gotta remove the trunk and the plate under it. Big long 12 pin connector is the main feed.
 

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I had the same problem. No horn, no brake light and no alarm. All on the same fuse. See post below. I finally had to disconnect the alarm.


TwoTrike
Junior Member Join Date: Jan 2006
Location: DeKalb, Illinois, USA
Posts: 9

fuse blowing

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I just went through this problem with one of my 2005 trikes. The problem is the alarm system has gone bad. You need to remove the upper trunk, the thr cover plate under the trunk. There you will find the alarm system and the fuel vapor cannister system. Find the power connector to the alarm. It is a 3 wire plug and should have a red wire with a white stripe. Unplug that connector and then try a new fuse. Your brake lights and horn should come back. The only problem is if you have the alarm system set to cut the fuel supply you may not be able to start the bike. If thats the case you will have to replace the alarm system. If you don't have it programmed that way then you can cut the red wire and that will get rid of the short. You still have to leave the connector and all the rest of the connectors pluged in as one of those 3 wires in the power is some kind of senser wire and the bike will not start with it unplugged. If this works for you as it did for me you will have your bake lights and horn back but you will not be able to alarm the bike or use the electric locks which function from the alarm system. every thing else should work fine. If you need further held with this please feel free to call me at 815-793-8035 or email me at [email protected]. I hope this works for you as it did for me. I have a Clymer manual with color wiring diagrams so I may be able help you further. Have a good one.

Robert Erickson
__________________
Robert & Maureen
DeKalb, Illinois
05 K1200LT Hannigan Trike (Yellow)(M)
05 K1200LT Hannigan Trike (Blue)(R)
 

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2005 K1200LT
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If you do find it is the alarm you can bypass it. Just pull the 12 pin alarm connector and jump pin 3 (black/white/yellow) to pin 11 (black/yellow) and then pin10 (green/violet) to pin 6 (blue/violet). This enables the engine electrics relay and the fuel pump relay just as if the alarm was in there and operating.
 

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Discussion Starter · #11 ·
Thanks guys for the ammunition for todays mission, gonna try some ideas today. Have all but the bottom tupperware off now. I though I did disconnect the alarm but must have missed the 3 wire connector going to look for it now thanks, I'll report progress tonight.
 

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Discussion Starter · #12 · (Edited)
what does ECHS electronics stand for? Can't find that one? The good news is you are correct, unpluging the 3 wire harness did the trick no more blown fuses, to verify it was the alarm I sacrificed one more fuse to prove it! I just need to do the other things with the by passing of the wires as you stated, this shold be a real trick. Thanks guys, I'll keep you posted.
 

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2005 K1200LT
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EHCS (I am dyslexic sometimes). Electro Hydraulic Center Stand. There is a controller on the rear fender on the right side. One of my diagrams is wrong in that it showed that also on the fuse.

Guess there is a rash of alarm issues going around.
 

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The big irony. I'm willing to bet more guys went without their bikes because of defective alarm systems than guys who got their LT stolen. Seriously, has anyone ever had their LT stolen? No offense to anyone, but I don't see it as a big theft item. Not where I live anyway.
 

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deanwoolsey said:
The big irony. I'm willing to bet more guys went without their bikes because of defective alarm systems than guys who got their LT stolen. Seriously, has anyone ever had their LT stolen? No offense to anyone, but I don't see it as a big theft item. Not where I live anyway.
I had those same thoughts.
Something more to go wrong also!
 

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Discussion Starter · #16 ·
I must say, you guys have come thru as always. I still have to jump the wires to get the starter to work but that is coming from KGT1200. Thanks Robert. I have noticed a few threads on this. When I searched I didn't find any as I was looking under brake. The real culprit is the alarm system somehow. Now all I did was let the battery go dead this winter as it was about dead anyway. Somehow, from the threads I read, this seems to be something common for to make the alarm system fail. Sounds like the blown rear end thread all over again. BMW seems good at designing things that fail intermittantly and keeping their dealers in business. I've had more than my share of failures on this bike, I love it dearly but I can't buy another BMW, not that I'll ever have the funds again. Cost too much. In 99,300 some miles I have had the hydraulic stand fail twice, don't use it anymore, rear wheel drive failure, clutch/oil seal problem, fried wiring harness and all the parts that burned up also, 2 rearrotor failures,one the new one they installed to replace it and refused to fix under the 2 year period they are supposed to honor, bought a 3rd put on myself, fail, throttle actuator idle sensor, radio/cd/failure, 3 seats that shed their threads, the 2 rear speaker arm rest fell apart, radio antenna broke, and left front fork seal blew recently. That's all I can think of offhand.
If it weren't for this site and the fact I can do my own work I would never have got it running after year 2. A few things got fixed under the extended warranty but others that should have didn't because I didn't know if it was an Oil seal failure or the clutch was just bad and couldn't afford 2000.00 bucks to replace a clutch if it was that and not the oil seal. That said I REALLY appreciate you all on here.
 

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Discussion Starter · #17 ·
Have the bike back together and now I have no blinkers, is that normal? Thanks.
 

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2005 K1200LT
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No it is not normal. The alarm does tie into the flasher unit as it uses those light for arm disarm signal but bypassing the alarm should not interupt flasher function Check your four way button (key on) and see if that part is working.
 

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Discussion Starter · #19 ·
I checked the 4 way flashers, they don't work either. I still have the 3 wire to the alarm UN-PLUGGED is that the reason possibly? I have a used alarm coming on friday from ebay that I will install and all the resident problems I will have setting the codes and such if I even have to. I just did the pin jumpers for now. I didn't want to cut the wire and I didn't jump the other 2 wires in it. That's probably it, RIGHT??
 

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2005 K1200LT
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I am afraid the three pin connector has nothing to do with the flasher unit. Also the flasher unit it is fed power all the time with no inline fuse( that I can find on the diagrams ). Hope the bad alarm didn't take out the flasher unit ($120).
 
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