3rd brake light
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3rd brake light
My 78 f250 doesnt have a 3rd brake light and i would like to install one. I want a clear lens with chrome or black brake light. I want it bright but dont want it to blind the people behind me. Anyone know of one that will work and match the contour of these cabs?
Also i want to wire it so when i open the doors it turns on. Im assuming i tap into the dome light as its right there? Can i have it turn on with the brakes and doors open or can i not tap into 2 seperate locations?
Also i want to wire it so when i open the doors it turns on. Im assuming i tap into the dome light as its right there? Can i have it turn on with the brakes and doors open or can i not tap into 2 seperate locations?
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You'd want to go with a light that has separate bed lights built in then; otherwise, your brake lights and dome light would always come on together when either is actuated, if you tie them together. Alternatively, you could rig up a second door switch in parallel to turn it on, or rig up some sort of diode-isolation circuit between it and the dome light, but you wouldn't want to tap into the dome light directly.
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From: Knoxville, TN
As for the light itself, the center high-mounted stop light (CHMSL) is the official name for them in government regulations - in the US, they became mandatory for passenger cars in 1986 and for light trucks in 1994. Nothing from this era had one; you may be able to make something from some other truck work, but trucks didn't come with them until nearly 20 years after yours was built, so a direct-fit doesn't exist.
That said, there were optional bed cargo lights available on these trucks, so you could maybe find one of those, set it up with a red LED bulb, and wire it up... though I'm not sure your truck is likely to sit low enough to the ground that semis can't see your normal brake lights (which was the reason for their use to begin with).
That said, there were optional bed cargo lights available on these trucks, so you could maybe find one of those, set it up with a red LED bulb, and wire it up... though I'm not sure your truck is likely to sit low enough to the ground that semis can't see your normal brake lights (which was the reason for their use to begin with).
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The main purpose i want it is so when i open the doors it turns on to light up the box. The box will also have led strips inside it that come on with the door open. Doesnt matter much if it comes on when the brake pedal is applied. My 87 f150 has a 3rd light, i swore it was factory. Maybe not though.
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From: Knoxville, TN
Yeah, cargo lights were available for these - though from the factory they were controlled by a manual switch, not tied into the dome light circuits. Doesn't mean you couldn't wire them up to the dome/courtesy lights if desired.
https://www.npdlink.com/store/?p=cat...t=50000&year=0
Truck Parts and Truck Accessories
https://www.npdlink.com/store/?p=cat...t=50000&year=0
Truck Parts and Truck Accessories
Fleet Owner
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From: NorCal
Bkaul posted the links for the switch and the light....use 'em.
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I looked at those links. Is the location of the switch correct? Behind the seat in door pillar? Thats how my 87 is but p.o mightve added it.
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From: Wildwood Pa
You have to watch how you wire a 3rd brake light on older vehicles.
You cant hook it up to either side rear light(s) without a "black box" as it will blink with the turn signal and back feed thru to the other side.
You can run a wire back to the brake light switch before the turn signal switch.
Light with the module: Accessories : Universal 3rd Brake Lamp with Stop Logic Module
You cant hook it up to either side rear light(s) without a "black box" as it will blink with the turn signal and back feed thru to the other side.
You can run a wire back to the brake light switch before the turn signal switch.
Light with the module: Accessories : Universal 3rd Brake Lamp with Stop Logic Module
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Im not doing a brake light now. Just going to do the factory cargo light but i need a pic of the factory location for the swtich. My only truck that has the switch is a 87 not sure if its the same.
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As luck would have it, there's a picture in this post that shows the cargo bed switch position... https://www.ford-trucks.com/forums/1...lp-needed.html
Last edited by notthemaniusedtobe; May 4, 2015 at 06:08 PM. Reason: Additional info.
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From: Knoxville, TN
I think he actually wants it as a cargo light and was just asking about a 3rd brake light since he didn't realize that was an option.