Author Topic: Turn signal goes on and opposite brake light goes out !!!  (Read 4757 times)

DAVEN1256

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Turn signal goes on and opposite brake light goes out !!!
« on: March 06, 2022, 10:53:54 PM »
Hopefully someone with more electrical knowledge of these cars than myself can point me in the right direction on as to where the trouble is.

When you apply the brakes, both brake lights light up as they should.

With the key ON....and the brake lights on, when the right turn signal is turned on, the right turn signal/brake light flashes as it should but the left brake light goes out.

Also, if the key is OFF.....and the brake lights are on.....if the right turn signal is turned on, both brake/turn signal lights go out.......If the left turn signal is turned on, only the left brake/turn signal light goes out and the right one stays lit.

Any ideas?

Thanks......Dave

rich69rs

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Re: Turn signal goes on and opposite brake light goes out !!!
« Reply #1 on: March 07, 2022, 04:47:38 PM »
Need a little more information.

Original harness?  New harness?  Any wiring modifications?  When did this begin?  Any wiring modifications updates just prior to this beginning? 

I would begin by making sure all connections and grounds are solid and tight. 

I would then remove the brake/turn signal bulbs on the right side, turn the key on, brake lights on, turn on the right turn signal and see if left brake light goes out with the right side bulbs removed.

This might help try to isolate source of the problem and it is an easy thing to check.

Richard
Richard Thomas
1969 RS

ko-lek-tor

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Re: Turn signal goes on and opposite brake light goes out !!!
« Reply #2 on: March 07, 2022, 04:50:54 PM »
Ground problem. Period
Bentley to friends :1969 SS/RS 396 owned 79
1969 SS 350 (sold)
1969 D.H.COPO replica 4spd. owned since 85
1967 302 4 spd 5.13

DAVEN1256

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Re: Turn signal goes on and opposite brake light goes out !!!
« Reply #3 on: March 08, 2022, 01:49:01 AM »
Thanks for the replies and input so far.

This problem actually dates back many, many years to before this restoration started. At that time, the car was at an auto electric shop for another problem. I asked them for an opinion on this problem. They thought the problem was "inside the steering column." That was just their opinion at the time. It never went back to the shop for them to dig into it and then the car went into hibernation for many years.

During this restoration, the only thing that has been changed electrically is that both of the under hood wiring harnesses and the wiring harness going to the tail panel lighting were replaced with original style harnesses from AAW. Other than that, everything is everything else is exactly the same. The wiring harness under the dash is the original. Everything else electrically on the car is working fine.

I checked the grounds on the tail/ brake/turn signal lights and they all seem to be fine.

Problem does exactly the same thing with the headlights on.

Front turn signals and signal indicators on the dash work fine with the brake lights on or off.

Wiggling the turn signal lever doesn't show anything out of the ordinary.
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Right now, I'm inclined to order a new turn signal switch but is there any other ground points should I be checking besides what I already checked first?



Thanks ......Dave

rich69rs

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Re: Turn signal goes on and opposite brake light goes out !!!
« Reply #4 on: March 08, 2022, 02:36:04 AM »
I’d still pull the bulbs on the right side and see if problem still exists with the bulbs out.

Richard
Richard Thomas
1969 RS

DAVEN1256

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Re: Turn signal goes on and opposite brake light goes out !!!
« Reply #5 on: March 15, 2022, 03:16:51 PM »
I got my new turn signal switch yesterday. I unplugged the harness of my existing switch (still in the steering column) from the connector under the dash and plugged in the new switch.


It solved my original problem of the left brake light going out when the right turn signal was turned on. The brake light stays lit like it should.

However the new switch gave me a new problem that I didn't have before.....With the key on or off and the turn signal switch in the off position, the right front signal light in the grille and the right turn signal indicator in the dash are blinking however the right turn signal/brake light is not blinking.

Turning on the flashers on or turning on the right turn signal with the key on will override this and all the lights on the right will blink as they should. If you turn on the left signal, all the lights on the left will blink as they should, however the problem on the right still persists. The front turn signal light in the grille and the right turn signal indicator in the dash are still blinking along with all of the lights on the left.....and also the left and right side are out of sync with each other and blinking at different speeds. The flashers blink at a much slower speed that the turn signals and this blinking problem on the right blinks at the same speed as the flashers.....for whatever that's worth.

When I disconnect the new switch and plug the old one back in, everything goes back to how it was before.....All lights functioning perfectly except for the left brake/turn signal light going out when the right turn signal is turned on.

The switch is by American Autowire. It is their p/n 07800482. It lists many applications that includes '68 Camaro "without column shift auto trans, with or without tilt." I have a tilt column.

New switch bad? Any other ideas? I have none.



olddragracer

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Re: Turn signal goes on and opposite brake light goes out !!!
« Reply #6 on: March 15, 2022, 08:37:08 PM »
Reads like you are having a problem with the traffic hazard circuit or switch. [4 way switch]  Reads like you have solved part of your problem with the new turn signal switch.

DAVEN1256

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Re: Turn signal goes on and opposite brake light goes out !!!
« Reply #7 on: March 21, 2022, 03:41:08 PM »
It turns out that the replacement switch I got was defective.

There was a short circuit in the switch between the dark blue and brown wire. The blue wire feeding the right front turn signal light in the grille and the right turn signal indicator in the dash....and the brown wire going to the hazard flasher....hence, those two lights flashing even when the turn signal and hazard switches were off.

I bought the new switch from The Parts Place. I called them and they were great. They put a new switch in the mail that same day and included a return shipping label for the defective switch.

The new switch came today. I plugged it in and everything is fine. No short circuit in this switch and my original problem (why I bought a new switch in the first place) of the left brake light going out when the right turn signal went on is gone.

Thanks for the help......Dave