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Third brake light stays on

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Old 04-08-2022, 02:25 PM
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Third brake light stays on

Ok here is this weeks problem. I depress the brake pedal and all the brake lights work. When i release it the high third stays on. Could it be the brake switch at the pedal? Or is there a relay that could be bad?
Old 04-08-2022, 02:59 PM
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Re: Third brake light stays on

If it was the brake pedal switch, all 3 would stay on.

Maybe a loose connection to the third brake light.
Old 04-08-2022, 04:08 PM
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Re: Third brake light stays on

Originally Posted by topduarte
If it was the brake pedal switch, all 3 would stay on.

Maybe a loose connection to the third brake light.
Actually, no, the brake light switch is two independent switches driven by the same plunger, as this handy dandy wiring diagram shows. The section controlling the third brake light could very well be sticking closed while the regular brake light portion still works properly



Last edited by OrangeBird; 04-08-2022 at 06:58 PM. Reason: damn typos ;)
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cjh1505 (04-08-2022)
Old 04-08-2022, 04:18 PM
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Re: Third brake light stays on

Originally Posted by OrangeBird
Actually, no, the brake light switch is two independent switches driven by the same plunger, as this hands dandy wiring diagram shows. The section controlling the third brake light could very well be sticking closed while the regular brake light portion still works properly


thanks for the info. Looks like im going to try replacing the brake light switch first.
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Old 04-08-2022, 04:29 PM
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Re: Third brake light stays on

Originally Posted by cjh1505
thanks for the info. Looks like im going to try replacing the brake light switch first.
Your welcome
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Old 04-20-2022, 01:28 PM
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Re: Third brake light stays on

Originally Posted by OrangeBird
Your welcome
got the new brake switch. It wasnt the problem. One on the connectors on the rear hatch struts fell off. Drove myself nuts over a lose connector. 🤦‍♂️
Old 04-21-2022, 11:48 AM
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Re: Third brake light stays on

Originally Posted by cjh1505
got the new brake switch. It wasnt the problem. One on the connectors on the rear hatch struts fell off. Drove myself nuts over a lose connector. 🤦‍♂️
Hi cjh1505, thank you for posting up the solution of your problem, my apologies it wasn't the switch and i'm left wondering if a grounding problem still exists. Perhaps if the ground isn't right somewhere, when the contacts went bad the light "backfed" through the rear defroster somehow, since the connectors on the rear hatch struts are supposed to be for the defroster only? Anyway, I'm happy to hear you've got it sorted.....
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