Just adding that this got solved :  took apart the switch and cleaned it (was all greasy) and now everything works!

 

Hey there folks,  ,
   Gonna jump on this 2yr dead thread.

  Pretty much the exact same scenario as the Author experienced.  I've replaced all the turn signal components w/LED lamps and flasher(EP-35 Napa).
No in-line resistors.  Cleaned the left side switch and lubricated it with graphite spray.

   A faint light at the lamps. No flashing.

   The other components off the switch work fine( hi/low beam; horn; flash to pass).

  My next plan is to look for voltage to the lamps and the flasher.
Other than replacing the flasher again,  , I'm scratching my head!   Help me please.   G.

Update::
   
   Did another system check, ,
Wiring;  connections;  continuity;  ground; etc.   All good and proper.  Installed another flasher/relay (Novita EP-35) $12.99 from O'Reilly's auto parts.
  Now I have functional signals L/R,,  until.
I connect the instrument panel. 
When I activate the switch,  I have a 4 way flasher.
  All the wiring inside the switch and  instrument cluster is in excellent condition,  replaced the cluster bulbs.  All tested good.
    [bang]I'm pretty much stumped.   Any thoughts,  ideas and suggestions are welcome.  Please.  Thanks,,  G.