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Discussion Starter #1
I have 2002 LT. When turning the ignition key to the start position and then squeezing the front brake handle I hear a whine then brake lever will stiffen up which is the normal sequence. This seems to be the brake power assist kicking in. Is the power assist the ABS control unit or some other device? Does pressing the brake lever give an electrical signal to the abs/power assist or is it activated by brake fluid pressure. The reason I ask is on occasion when I turn the key to start position and press the front brake handle the lever goes soft and the red triangle brake light comes on, no power assist. I then turn the key off then back to the start position and everything works as normal. Brake fluid levels are good at both the rear and front reservoirs. Seems the problem only occurs during the first cold start and everything is fine on subsequent starts. Battery is good and fully charged. I even get the red triangle and soft lever (no power assist) even after the bike is started, but again only occasionally with the first cold start. I have not had the bike at the dealer to see if there are any faults being recorded, but that will be my next step, unless someone can tell me what to else to check.
Thanks
Joe
 

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Mines is an 09 and that will happen if you grab the handle before the system has pressurized can be something of a problem if you're on a slope
 

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Wrencher Extraordinaire
2005 K1200LT
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The system needs to perform a "no pressure" self check first. That means hands off the brakes (leave it in gear if on a slope) until the initial check is done. During this initial check the lights will flash rapidly. If you don't adhere to this it will never go to the second level. Once they go to a slow flash (second level) you can then apply the brakes. That slow flash should go out after you have traveled a short distance.
 

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rovero said:
I have 2002 LT. When turning the ignition key to the start position and then squeezing the front brake handle I hear a whine then brake lever will stiffen up which is the normal sequence. This seems to be the brake power assist kicking in. Is the power assist the ABS control unit or some other device? Does pressing the brake lever give an electrical signal to the abs/power assist or is it activated by brake fluid pressure. The reason I ask is on occasion when I turn the key to start position and press the front brake handle the lever goes soft and the red triangle brake light comes on, no power assist. I then turn the key off then back to the start position and everything works as normal. Brake fluid levels are good at both the rear and front reservoirs. Seems the problem only occurs during the first cold start and everything is fine on subsequent starts. Battery is good and fully charged. I even get the red triangle and soft lever (no power assist) even after the bike is started, but again only occasionally with the first cold start. I have not had the bike at the dealer to see if there are any faults being recorded, but that will be my next step, unless someone can tell me what to else to check.
Thanks
Joe
If your warning light comes on, then you may have air in your brake fluid lines or not enough of liquid.
Normally, the warning light does not come on, unless something is not right. I would check the brake system if I were you.
BJ
 

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Double-check your rear reservoir level again -- on the pre-'05 LTs, if the rear level is ok, but on the low side of "ok," you can be right on the "knife-edge" of the rear low level sensor triggering when the bike is cold. That will result in the ABS computer declaring a "fail" on the start-up testing. With just a bit of heat and/or movement, the sensor clears, so a restart will restore the brakes. This can explain why your problem goes away with another key off/on cycle.

It is not uncommon to see a few of these reports every year as the fall/winter temps begin to drop. A cc or 2 in the rear reservoir is often enough to fix the issue.
 

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thanks ' mneblett
"It is not uncommon to see a few of these reports every year as the fall/winter temps begin to drop. A cc or 2 in the rear reservoir is often enough to fix the issue."

Seen these issues reappear year by year.
 
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