So I added led rear lights and 3rd brake light, no hyperflash. Then I added toe mirrors with ked signals and now have hyperflash on the driver's side. I added an ked flash module under the driver side dash, didn't work. Added a resistor to the rear light, didn't work. Added a resistor to the tow mirror, didn't work. Added a resistor to the rear light and the tow turn signal, gave me a dead flash.

I honestly don't know what to check anymore. Anyone have any thoughts?

 

...

 

Only thoughts I have are what you are driving? Post your trucks year, engine, trim level eg: Lariat, Xlt etc...

The more information you give will filter out any guesses. No two trucks are the same even with the same trims, engine, etc.... so we need to be more specific when we ask for information.
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Duh me. 2004 FX4 crew cab

 

Anyone?

 

What LED flasher unit did you install.. ? EP27

 

Yeah I put in the EP27

 

Only other thing I can think of is you have a burnt bulb somewhere.

 

Nope, all my bulbs are good.