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bobsmanstuff 04-10-2020 06:53 PM

brake light

Hi guys, still have the same problem with my brake lights. Without stepping on the pedal the brake lights are on and when I step on the pedal they go out. Some of the wires looking iffy so rewired the lights and brake light but still the same. Put a different switch same thing. Would a ground wire from the battery to the frame help? I'm stumped. thanks for any advice-Bob

CT Jack 04-10-2020 09:06 PM

Re: brake light

#1 Test the switch - disconnect all wires from switch. Using an ohmmeter or multimeter place one lead on one terminal and the other lead on the 2nd terminal. The meter should indicate the switch is open, no continuity. Slowly press on the brake pedal and watch when the meter responds or indicates making contact or continuity. If the meter responds accordingly, the switch is good.
#2 Connect (-) 6 volt wire from battery (not ground) to left screw terminal. Using meter on dc voltage setting touch (-) probe to 2nd terminal and the (+) probe to ground. You should see 0 volts. Depressing the pedal the meter should indicate 6 volts. This proves the switch is working and the brake pedal connection is adjusted properly.
#3 Test light socket - Connect the stop light wire (-) going from the switch to the 2nd terminal on the switch. Remove the lamp from stop light. Connect the meter as in step #2 (one probe on the lamp socket contact and the other probe touching ground). The meter should indicate 0 volts. Have someone step on the brake pedal and the meter should read 6 volts. If this test fails you have a wiring problem or a poor ground.
I recommend soldering a wire to the outside of the lamp base and screw connecting it to a body member. This will guarantee a good ground. The lamp bracket usually has a rubber gasket. This can insulate the lamp base from being grounded properly.
Install the lamp and it should work.

bobsmanstuff 04-10-2020 09:33 PM

Re: brake light

Thanks I'll give it a try tomorrow.

KGBnut 04-11-2020 07:06 AM

Re: brake light

Did you recently replace the switch? The reproductions are iffy at best. Also, if I remember right, the early switches were mounted as pull switches, and the later as push switches. Make sure it is mounted correctly.

Patrick L. 04-11-2020 09:15 AM

Re: brake light

It helps to know which switch you're using. 28-29 and 30-31 are different and in different locations. 30-31 are normally closed and 28-29 are normally open [ if I remember correctly, but, thats an easy check].

Just take a test light or volt meter and check when you have and don't have power. There should be constant power to the switch and power to the lights only when the switch is activated.

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