Rear brake light no worky - LC4

Discussion in 'Thumpers' started by Beez, Jun 21, 2007.

  1. Beez

    Beez Given to fly

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    The rear brake is not activating the brake light on my 1997 620 RXC. The brake light works fine with the front brake and if I touch the two wires that connect to the rear brake pressure switch the light goes on. So I believe the problem lies in the pressure switch.

    My question is how pressure switches work? Do they just go bad? The rear brake is long overdue for a fluid change, will a fresh bleed make the switch work again?
    #1
  2. Odysseus

    Odysseus Stoic Philosopher

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    A fluid change is cheap and easy to do, so it couldn't hurt. But it won't fix a broken pressure switch.

    Have you done all the easy things like check all wires/connections, and the fuse? A check with a multimeter should tell you what the problem is very quickly. :deal
    #2
  3. Beez

    Beez Given to fly

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    I have checked the wires. I removed the two wires from the pressure switch, touched them together and the brake light goes on. I don't think it is a wiring failure.

    I have a multimeter but don't really know how to use it other than checking the voltage of a battery. Ohms and resistance is BFM to me.*

    *Black Fuckin' Magic :dunno
    #3
  4. KTMax m AL

    KTMax m AL Fagarwe tribal member AL

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    You have solved your own problem - the switch is bad.:deal

    To use your multimeter to check the switch set the selector to ohms (ohms are a measure of resistance to electricty within a circuit - your brake light switch). With your wires removed from the switch set meter to a low value on the ohms section and hold a test lead on each post of the switch. The meter should show no change - now press your brake lever and if switch is good meter display will change to (0) zero. If switch is no good = no change on the meter.

    Easy as cake. IMO

    Good luck :ricky
    #4
  5. Beez

    Beez Given to fly

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    I'm more of a pie man. :dg

    Thanks, I'll try that tonight!
    #5
  6. dorkpunch

    dorkpunch Oops...

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    while we're on the subject of brake lights... any idea why my signals/dash lights dont work unless BOTH front and rear brakes are pulled? The brake light will work with the front brake pulled, the back brake pulled, or both, but the signals etc dont work unless both are pulled. :huh
    #6
  7. clintnz

    clintnz Trans-Global Chook Chaser

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    Funky shite like that is almost always an indication of a bad earth somewhere.

    Cheers
    Clint
    #7
  8. twowheelneil

    twowheelneil n00b

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    Sorry in advance if I am on the wrong thread but this is the closest thing that I could find to the issues that I am having.

    So about a month ago I bought a 1995 ktm lc4 620 RXC. It was sitting for 3 years before I bought it so I got it cheap. I cleaned the carb, adjusted the vavles, changed the oil and coolant, bought a new battery, bought a new petcock(old one was corroded) and some other things that are probably slipping my mind. Regardless, it runs perfect and I couldn't be more thrilled to have a solid dual purpose bike. But, for some reason the headlight (bought a new one) doesnt work and the brake light wont turn off even when I have taken the key out of the ignition which obviously is draining my new battery. The blinkers work perfectly along with the blinker light on the cluster. The horn works while the engine is at speed (Im assuming the stator isnt the strongest). The kill switch works as well. The neutral light wasnt turning on nor was the high beam indicator. Im just trying to think of anything that could be important. I own a voltage meter and have tested nearly everything that I could think of but havent figured anything out!

    Any advice or suggestions would be greatly appreciated!!
    #8
  9. gravityisnotmyfriend

    gravityisnotmyfriend Long timer

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    Feel free to start your own thread. No need to resurrect a 5 year old one.

    I've got a '94 620, so I'm hoping it's similar enough to yours to help. How many positions does your ignition switch have? You can put the key in the "park position" and pull it out. This will cause the tail light an a small light in the headlight to remain on. One click clockwise from park is "off". You should be able to pull the key out in this position too - but the tail light should be off. If that's not the case, there's something wacky going on.


    As for the headlight. My bike has a three position switch on teh LH grip. All lights off, headlight off (the rest of the lights on), and all lights on. Make sure it's in the right position.

    My headlight only illuminates when the bike is running, so make sure you start it and then check the lights.

    If all of that checks out, pull your headlight and check to make sure that it isn't burned out. I'm in the process of replacing the voltage regulator because my bike will blow a bulb as soon as it's started.
    #9
  10. twowheelneil

    twowheelneil n00b

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    Im definitely taking the key out in the 'off' position but I had no idea that the key could be taken out in the 'park' position. That would explain the parking light im assuming? I am going to look into that switch because the writing that would tell me where my light switch should be positioned is faded so I cannot read it. Hopefully that is the issue! Ill go ahead and start a new thread. Thanks for the direction and I hope that you get your issues sorted out.
    #10
  11. Queen of Spades

    Queen of Spades tall drink of water

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    Shit. Nevermind. Noticed the post dates. deleeeeted.
    #11