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Old 10-28-2013, 06:36 PM   #1
pick
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Default brake lights are on on on

brake lights are on whenever the battery is connected. the pedal linkage has been checked all out, brake switch has been replaced. whenever the battery is connected the brake lights are on even when the wires are disconnected from the brake switch. what's up? any ideas? where do I start?????
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Old 10-28-2013, 06:43 PM   #2
Mitch//pa
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Default Re: brake lights are on on on

Are you sure its not the tail lights which are red // the brake lights are amber
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Old 10-28-2013, 06:49 PM   #3
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Default Re: brake lights are on on on

Has the lights been worked on? Did this just start?

Take a volt meter or test light and check each side of the switch. One terminal will have voltage to the frame the other sould not. If both are hot remove the wire heading to the rear of the car. Check the terminal you removed the wire from it should showing no voltage to the frame. If it still is hot = bad switch. If the switch is dead wireing wrong. Check this and let us know. Pm me if you wish, Phil
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Old 10-28-2013, 06:49 PM   #4
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Default Re: brake lights are on on on

definitely the b rake lights
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Old 10-28-2013, 06:52 PM   #5
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Default Re: brake lights are on on on

i'll check the wiring/switch tomorrow night as you suggested obviously electrics are not my forte.....
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Old 10-28-2013, 06:55 PM   #6
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Default Re: brake lights are on on on

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fyi this is a new project I just purchased and it didn't have this problem until last time I drove it
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Old 10-28-2013, 07:06 PM   #7
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Default Re: brake lights are on on on

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brake lights are on whenever the battery is connected. the pedal linkage has been checked all out, brake switch has been replaced. whenever the battery is connected the brake lights are on even when the wires are disconnected from the brake switch. what's up? any ideas? where do I start?????
Can't be the switch, as it's now out of the circuit.
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Old 10-28-2013, 07:27 PM   #8
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Default Re: brake lights are on on on

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Can't be the switch, as it's now out of the circuit.
Thats what i read into it and figured maybe its the tail lights
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Old 10-28-2013, 07:38 PM   #9
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Default Re: brake lights are on on on

I have found that id the plunger arm is bent of the frame is, sometimes the plunger won't hit the brake switch.
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Old 10-28-2013, 08:11 PM   #10
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Default Re: brake lights are on on on

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Can't be the switch, as it's now out of the circuit.
Oops I miss read the original post. Didn't notice wires were disconnected from switch. Would be time to trace out the wires from the brake light to source. Sorry for the senior moment,Phil.
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Old 10-28-2013, 10:36 PM   #11
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Default Re: brake lights are on on on

sounds to me like the brake lights are being fed by the tail light circuit. Is the headlight switch off or in park position?
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Old 10-28-2013, 11:10 PM   #12
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Default Re: brake lights are on on on

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sounds to me like the brake lights are being fed by the tail light circuit. Is the headlight switch off or in park position?
I was thinking the same thing. Something has to be crossed for the brake light to be on with the switch out of the circuit. Maybe the two wires are crossed at the connection over the rear axle. That plus the switch being in some position other than off.
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Old 10-28-2013, 11:36 PM   #13
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Default Re: brake lights are on on on

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I was thinking the same thing. Something has to be crossed for the brake light to be on with the switch out of the circuit. Maybe the two wires are crossed at the connection over the rear axle. That plus the switch being in some position other than off.
Ditto!

Pick do you have a wiring diagram?

Wiring diagram.
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Old 10-29-2013, 01:16 AM   #14
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Default Re: brake lights are on on on

will this help? it's for 30/31
Attached Images
File Type: jpg img395.jpg (110.2 KB, 84 views)
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Old 10-29-2013, 02:13 AM   #15
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Default Re: brake lights are on on on

Brake light on when disconnected from the switch is a challenging mystery.

You have to find out where the electrical energy is coming from. It is not possible for the light to be on without electricity from somewhere. Somehow, someway, electricity is getting into the brake light wire.
My guess, strictly a guess, is the wiring bundle at the bottom of the steering column is somehow crossed or shorted. It is the only place I can think of that would supply the current, absent a major mistake. The repo switches are not very good at keeping the connections separated, but even that does not make much sense if the switch is unwired.
Assuming everything else is off, and double check that assumption, one way is to get a pal to watch the light, and start dis-connecting the wire, starting from the wire into the light and go forward, until it goes off. Or, by yourself, trace it with a voltage and continuity tester from the light forward.
I look forward to seeing the solution. Please keep us advised.
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Old 10-29-2013, 09:37 AM   #16
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Default Re: brake lights are on on on

repro/gyp parts????
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Old 10-29-2013, 10:41 AM   #17
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Default Re: brake lights are on on on

If he's got lights with the switch pulled from the column there could be a short inside the harness from the battery wire (on the starter) to the tail light wire. The harness is the only place where everything is together. The short could also be where the harness ties to the switch contacts.

Rethinking, there is also a hot wire in the harness to the brake light switch - those two wires could also be shorted inside the harness. This could be tested by removing both wires from the switch and measuring if there's voltage on both - only one wire should be hot.

This is an interesting puzzle!
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Old 10-29-2013, 11:14 AM   #18
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Default Re: brake lights are on on on

Do you have turn signals wired into the car? The turn signal uses the original brake light wire to flash the brake light on one side, plus an additional wire not in the original loom to flash the brake light on the other side. The output from the brake switch should be routed up to appropriate wire in the turn signal wiring harness so that when you step on the brake, juice is sent through the turn signal switch and out to the two wires to the brake lights. I'd be that somehow the turn signal wiring got crossed up so that the wires for the brakes are always hot.
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Old 10-29-2013, 03:00 PM   #19
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Default Re: brake lights are on on on

Could the battery be hooked up backwards?
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Old 10-29-2013, 03:03 PM   #20
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Default Re: brake lights are on on on

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Could the battery be hooked up backwards?
This may be a dumb question but why would the battery being hooked up backwards cause this problem?

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