Thermal flasher won't flash

[MrTruck805]

Hi all,

I have a buss flasher 552/536 - http://www.ebay.com/itm/BUSS-FLASHE...NSN-5945-00-849-1124-C5AZ13350A-/271220904601

I have the output hooked up to a 5 foot strip with 20 or so small LEDs. 12 volts passes through and constantly lights the LEDs, but they never turn off. I'm wondering if the LEDs are too efficient that they don't draw enough current that the flasher needs to shut off? I have a current clamp, so I can measure if need be.

Anyone have any insights? Thanks!

 

[diesel4me]

Your probably right in assuming the LED's aren't enough of a "load" to make the flasher flash...try it with a regular bulb to see if its good,if its flashes then,its got to be you assumed correctly..not sure how you'd remedy that either--add resistance maybe?...

 

[4xcrazy]

Try an electronic flasher.

 

[cybrfire]

Yep, been here and done that. LED's don't have enough load to make the switch do its thing.

Electronic flasher is supposed to be the fix. Ive had mixed results with them as well.

 

[cyclic]

On some regular flashers, open up the flasher housing, if it has an 8 pin chip in it, you can cut one leg and make a timed zero load flasher.
Here's a write up I did ages ago................
http://www.customfighters.com/forums/showthread.php?t=14822

It will allow a regular flasher to run zero load/LED's.

 

[Fordum]

That is a really common problem with LED replacements. Your standard 1157 brake light filament bulb draws about 2 amps per bulb.
Since there are more than one bulb in a blinker system, your flasher likes to see at least 2 amps, usually more.
Most places that sell LED replacement bulbs also sell load resistors that you can put across the bulb to draw enough current.

The most common is a 6 Ohm, 50 watt power resistor. It may tend to get hot, so it needs to be mounted to a piece of metal for heat sinking, and make sure its not against anything plastic.

You are better off with an electronic flasher if it works for you. No heat, no wasted power.
But, most of them do not make a clicking noise, so you might wind up with old fart's syndrome where you find yourself driving down the road with your blinker on for miles and miles.........

If you go with the resistor, remember, it goes across ( in parallel) with each of the bulbs.

 

[4xcrazy]

So far I've never had any that didn't click.

 

[MrTruck805]

Thanks for the replies! I soldered a resistor in parallel, and now I'm in business! I'll look into an electronic flasher as well.