Help with LEDs!!

deceive · January 15, 2004

I bought some LEDs for the front bumper lights before I get clear corners, well the side LEDs are those jam straits (194A), and they worked fine. Then I bought some 3157s for the larger corner signal, and things went south. the 3157 will work with the running lights, but when you use the blinker, the blinker goes crazy and starts clicking twice the speed and flashing the lights double time. So they work entirely, its just with the blinker on, the lights flash 2x the speed.

BTW the 3157s i bought off ebay, so they are probably no name, could that be the problem?

Thanks if anyone has any idea

HumanZoom · January 15, 2004

Acutally you'll have that problem with all LEDs...not just your no name ebay ones

When you use LEDs in your turn signals you'll need to purchase a standard heavy duty flasher module/relay (can be found at your local auto parts store)....like the ones you use for when you hook up the tail lights/signals on a trailer.

Be careful though if you are considering using LEDs as DRL replacements. I hear (and I'm sure other members of this board can testify to this) that they seem to blow a fuse or whatever, therefore causing further problems.

Good luck with your lighting system...I hope it works out for you.

SnakeEyeSS · January 15, 2004

also, if the refelctor pattern for your truck is not replaced with one specifically designed for LED's, the lights can be darker, INCREASING the chance that someone won't get the message yourt light are trying to tell them.

deceive · January 15, 2004

I'm still confused as to why the 194s worked fine. Also when I turned on the emergency lights, they all work perfectly

as far as that flasher thing you were talking about... is this what I need?

http://www.jamstrait.com/loadr.jpg

thanks..

HumanZoom · January 15, 2004

I thought they looked more like this:

but I could be wrong...never used them personally. I do know AutoZone sells them, so you might want to try there.

A little while ago I wanted to change out my taillights to be LEDs...wasn't satisfied with the look, but just for kicks before I returned them I popped them in the turn signals just to see what they would be like (esp. with a red LED cluster and an amber lense). The turn signal resulted in 2x the speed, but you're right...the hazard flasher's speed wasn't effected. I don't know why. And as far as the 194s not being effected I don't know why either. I assume 194s are the small bulbs next to the main turn signal that flash opposite when the lights are on...am I right or am I crazy? If so, I didn't know they made LEDs in that size...

MCourson · January 15, 2004

I thought they looked more like this:

Thats what you want.

Check this out:

http://www.gm-trucks.com/IAR_ElectronicFlasher.shtml

atomoverride · January 16, 2004

yeah blinking really fast, or not at all usualy points to that flasher unit.

deceive · January 16, 2004

basically the stock flasher isn't beefy enough to handle that load? I wonder if there is a heavy duty GM part that will work, since i've had quite a few bad experiences with a lot of autozone's "generic" aftermarket OEM replacement parts?

Sorry to be dragging this out, but there seems to be limited information this!

MCourson · January 17, 2004

You can not use the thermal type flasher. It will not work with the LEDs, you have to use the electric type.

Read This Article and it will tell you everything you need to know.

silverado3500 · March 31, 2004

The reason for this is actually because the LED bulbs draw LESS current than a standard light bulb. Your flasher like those most gm vehicles is designed so that if a turn signal bulb (either front or rear, or both) burns out it flashes at 2x normal speed, to alert the driver that a bulb or multiple bulbs are out. The hazard light power is fed through a seperate lead into the same flasher unit so that it will flash at normal speed when you use your hazards regardless of how many bulbs may be out.