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Old 01-08-2019, 02:47 PM   #1
VetteVet
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Re: Help with Brake lights

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Originally Posted by landarts View Post
Thanks for all the suggestions I will be doing some testing on Tuesday. Pretty sure it is not a ground problem at tail light since I have perfect blinkers that are bright and tail lights that are bright, just no stop lights.
Your assumption is correct on the rear lights.
If the lights are bright the grounds are good and the blinkers use the same wires and bulb elements that the stop lights use. So that tends to rule out the wiring to the rear lights. Stop ,tail. and blinkers. It only leaves power to the turn signal switch and the switch itself as possible problems.

If you confirm power to the switch on the white wire when the brake pedal is depressed, then the malfunction is in the switch or in the white wire from the connector to the switch. This wire powers both stoplights so it is possible that it is cut inside the column in the harness to the switch.

To troubleshoot this you can disconnect the column connector and locate the white, dark green, and yellow wires in the column half of the harness.
With a volt meter set for continuity, check for zero ohms between the white wire and the dark green wire and then the same between the white and yellow wire. This with the TS selector lever in neutral or centered position.

Power to the white brake switch wire originates at the fuse panel from the stop tail fuse. The orange wire supplies power to the dome light, the headlight switch (for the park lights, and the dash lights), and to the stop light switch.
See the diagram. Then the white wire from the stoplight switch goes to the column connector as has been described.

The voltage for the brake lights is constant and controlled by the switches so the key does not need to be on for them. VV
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Old 05-25-2019, 03:40 PM   #2
JDSurge
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Re: Help with Brake lights

I have a similar problem with the brake lights except, everything worked just fine a couple of days ago but now the brake, tail, and dash lights are out. I remember when I used to drive these old trucks and cars (1960's and 70's) that when the dash lights go out it means your brake and tail lights are out also. My blinkers work just fine and the brake fuse is good.
Not sure where to start looking now. Thought sure I blew a fuse.
Any thoughts?
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Old 05-25-2019, 08:04 PM   #3
Steeveedee
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Re: Help with Brake lights

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Originally Posted by JDSurge View Post
I have a similar problem with the brake lights except, everything worked just fine a couple of days ago but now the brake, tail, and dash lights are out. I remember when I used to drive these old trucks and cars (1960's and 70's) that when the dash lights go out it means your brake and tail lights are out also. My blinkers work just fine and the brake fuse is good.
Not sure where to start looking now. Thought sure I blew a fuse.
Any thoughts?
JDSurge
I think you should start a new thread for this, because you're going to get people answering questions from stuff that is posted above, and it will get confusing.
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Old 05-26-2019, 09:24 AM   #4
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Re: Help with Brake lights

Good idea Steeveedee. Im kinda new to this site and wasn't sure how to start a new one but I'll read a little to find out.
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