Emergency flasher lights 1979 GMC truch REVISITED

A couple of you replied about my emergency flasher problems on my 1979 GMC 7000. Spent a few minutes today checking out the connector strip at the base of the steering column. Found the power for the regular turn signals. And it has power only when the switch is on. Found the left turn signal wire and the right turn signal wire. Found the horn wire. I believe you guys said the brown wire should be for the emergency flashers. I assume the brown wire should light up my test light at the splice? Right? It doesn't. Or, is the brown wire on the ground side? If the brown wire is on the positive side shouldn't I be able to run a hot wire to the brown wire and make all of the flashers work (operate in solid light not blinking) if the emergency flasher switch is pushed in?? What are the other wires for?? There is one next to the horn wire I don't know what it does. Also, I think there is another wire down past the L and R turn signal wires I didn't figure out. Remember the L and R turn signals work as they should. The horn works. The emergency flashers did work late last summer. Once in a while when I push the emergency flasher button in I am sure/think the flasher switch might make a blinking sound once or twice. Any other ideas? Any tests I should run? Thanks - Andy

Did you try replacing the emergency flasher unit? I think there is two. One for the turn signals and one for the fourways.

Yes, there are two blinker units. I have switched them around and they both work in the regular turn signal position.

Hey Andy,

Brown wire is the hot side.
"brown wire should light test light at the splice." maybe, depends on the flasher, some are normally closed and some are normally open. Jumper the flasher and push the hazard switch. All four T/S-Haz lights should come on steady.

Make sure your haz flasher is a heavy duty type rated for at least 6 T/S lights.

Just an FYI in case you don't already know this, here are the rest of the color codes in the ribbon cable to the T/S switch.
purple- T/S feed from T/S flasher
brown- haz flasher
white- power feed from brake light switch
dark blue-feed to RH T/S lamp
light blue- feed to LH T/S lamp
green- feed to RH T/S and brake lamp
yellow- feed th LH T/S and brake lamp

I don't recall from your previous post but I believe you have replaced the T/S switch. Be sure you have the right one. There are at least TWO different pinouts for the harmonica connector on the end of the ribbon cable.

After all that, I still think you have a bad, corroded or loose connection.

The 4 way flasher could be bad and still work good flashing just two lights.