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TR2/3/3A LED turn signal -- panel flasher not working

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S

Snowkilts

Jedi Hopeful
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As the title says, I am converting to LED lights and can't get the panel flasher to work.

Specifically I have zero volts on the P terminal of the flasher. I bought a new flasher (SFB105) and still have zero volts on the P terminal. The actual flashers are working just fine.

Anybody have any ideas?

Other info: this is a positive ground vehicle. I kept the mechanical flasher and put a 3.3 ohm 50 watt resistor on each of the flasher circuits to create a load for the flasher. As I said the flashers work fine. I also can get the panel light to light up by connecting the light green wire from the flasher directly to the negative terminal of the battery, but of course this doesn't help without voltage coming from the P terminal.
 
I took the new flasher apart to see if I could figure out why the "P" terminal isn't working. Guess I needn't have bothered with all that nonsense of wiring in shunt resistors so I could use the "old style" flasher. :mad:

20210131_002348.jpg
 
What is the P terminal supposed to do? I'm not familiar with this circuit.
 
Are you saying if I get a modern flasher I could use led lights because the voodoo is already there in the flasher. I remember some threads years back where people had trouble using led in flasher system. I thought maybe it was in the interrupting circuit would not cut in and out.
steve
 
sp53 said:
Are you saying if I get a modern flasher I could use led lights because the voodoo is already there in the flasher. I remember some threads years back where people had trouble using led in flasher system. I thought maybe it was in the interrupting circuit would not cut in and out.
steve
Click to expand...

I thought that might work so I tried disconnecting the shunt resistors and basically putting the system back to stock except with the LED lights. The modern flasher did work, sort of. Instead of 50% on 50% off like you would want, it was more like 10% on, 10% on but dim, 80% off. So apparently even though the modern replacement flashers are electronic, they still don't work properly with LEDs without some kind of shunt resistor to pull some extra power.

After cutting apart both my new and old flashers and fettling it for a couple of hours I gave up and ordered a flasher from Litzupp.
 
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