mechanical brake light switch

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jimd60491
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mechanical brake light switch

#1

Post by jimd60491 »

when I engage the brake switch it cuts the lights off. release the switch they come back on all my other lights work and the bike is wired per the factory manual. could it be that the switch is grounding out. took the switch apart everything looks good not missing any parts. anyone else have this problem before
blewcrab
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Re: mechanical brake light switch

#2

Post by blewcrab »

remove the wires from switch ..... using a VOM check the switch to ground on both contacts .... if you read zero ohms on either contact to ground , you have a bad switch .... if you find the switch is open to ground ,remove the bulb ..check the wire going to the brake light ....if the brake lite wire reads zero ohms to ground check the brake lite socket or the wire going from switch to the brake lite ...... Hope this makes sense
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Re: mechanical brake light switch

#3

Post by RUBONE »

It sounds like your lighting circuit is grounding through the switch and applying it opens the ground circuit. Make sure the taillight and headlight are properly grounded to the frame, the taillight socket is grounded to the light body, etc. Paint is the worst culprit on most grounding issues.
doc9339
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Re: mechanical brake light switch

#4

Post by doc9339 »

If your mech switch is aftermarket, it could be bad. I have found allot of the A market mech switches are pretty much crap. But doing a check as mentioned will find that out
jimd60491
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Re: mechanical brake light switch

#5

Post by jimd60491 »

figured it out was missing a insulating washer on the backside of the terminal box behind the coil. everything is working now just got fix the tail light socket. brake light won't light up when the pedal is pushed getting power from the switch to the socket. thinking its the bulb not making contact with the wire
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