This maybe somewhere in the archives, but I didn't find the fix so here goes.

I have the newer style solid state flasher conversion on my truck. This has been an on again / off again issue for a couple years that started as a one off then started happening more and more over a couple of years to where now its almost just not working at all. You start out and it works fine (maybe), sometime later you turn it on and it may / may not work or decides to come on if you leave the lever activated, then goes off. Lately when I first flip the lever I get a quickie flash on the indicator light looking like it's trying to work then nothing.

I unplugged the connectors to make sure no gunk, etc.,. everything nice n clean, all wires are nice n tight, nothing there. I used a test light in a couple locations and have steady power going to the flasher and the switch lever; but when the flasher is unplugged, the front turn signal light bulbs and rears come on steady (odd). Also get a steady on with the indicator light on the turn signal lever.

Without anything else to go on I'm going to install a new flasher box and see if that is the fix.