LED Headlights, brake lights now don't work.

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Camcam1881
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LED Headlights, brake lights now don't work.

Post by Camcam1881 »

So I just recently picked up my first 1970 f250 and I'm starting to get her all buttoned up. The factory headlights and bulbs were terrible! I recently installed a plug and play led headlight kit and it works/ looks great. One thing I noticed is now when I press the brake the brake lights don't come on. It seems like they are constantly on. Any idea on where to look to correct the issue? Is it a turn signal led relay that I need to install will that correct the issue? Thanks!
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colnago
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Re: LED Headlights, brake lights now don't work.

Post by colnago »

On the brakes/signals, the current draw is much lower, so you can't just swap in LED bulbs. You might have to get a kit, so the resistance is equivalent to the old incandescent bulbs. I've heard that the LED bulbs can really screw up the blinkers!

Joseph

On edit, I just ran across this thread:

http://www.fordification.com/forum/view ... =8&t=76346
"Sugar", my 1967 Ford F250 2WD Camper Special, 352FE, Ford iron "T" Intake with 1405 Edelbrock, Duraspark II Ignition, C6 transmission, front disc brake conversion.
71Fe2O3
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Re: LED Headlights, brake lights now don't work.

Post by 71Fe2O3 »

Your brake light problem could be a result of the switch at the pedal being improperly adjusted. I guess it could also fail in the closed position if the spring inside weakens or breaks.

You will need a different flasher for LED turn signals. The stock flashers work by having a piece of wire inside that heats up as a result of the current going through it and intermittently opens and closes the circuit as the wire heats and cools. Because LED bulbs draw less current than the incandescent bulbs they are replacing, flashers designed for incandescent bulbs won't work properly on circuits with LED bulbs.

For the same reason, there is little to gain by installing relays on the brake light and turn signal circuits. The small number of low amperage incandescent lights on the brake, marker and turn signal circuits probably does not stress the switches on those circuits in the stock configuration, and because LED bulbs draw much less current than the original bulbs, there is even less of a potential benefit to be realized by installing relays on those circuits compared to high amperage loads such as headlight bulbs.
Fred

1970 F100 4WD short bed, 360 engine, very rusty plow and yard truck

1971 F100 2WD long bed, 302 engine, on the road

1968 F100 2WD long bed, 360 engine, stripping for parts
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Ranchero50
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Re: LED Headlights, brake lights now don't work.

Post by Ranchero50 »

Yep, to add what these folks said, LED's just don't look appropriate on an old Ford truck to me. I did do the cargo light to CHMSL / cargo light mod and it's nice there but...
'70 F-350 CS Cummins 6BT 10klb truck 64k mile Bahama Blue

Contact me for CNC Dome Lamp Bezels and Ash Tray pulls.
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