So I sold my truck earlier this week and I failed to mention that you have to ever so slightly move the key back after starting cause the starter stays running. (Been that way since I bought it and was never clueless enough to not realize that was happening). He drove three miles and destroyed the starter, solenoid, and the ignition switch was now permanently trying to power the solenoid even if you cut the truck off. So I replaced all of that- EVERYTHING. And by the ignition switch I mean the electrical switch with the spring located on the top of my steering column. This is a 1991 xlt lariat 2wd that of course has tilt. Now I’ve taken care of the starter problem and shouldn’t have to move key anymore. HOWEVER, at the same time the turn signals stopped functioning. I already replaced the fuse(which hiked out fine) and for giggles ohmed out every single fuse in my panel. I replaced the turn signal flasher as my immediate thought. The hazard flasher is in passenger side and still works-(I can hear it clicking and see all lights flashing). I went ahead and just replaced the multifunction switch. Still no turn flashing. On any side front or back. I’m at a loss. I’ve never had this issue and don’t know what is going on. I’m wondering if there is something that I’m missing that the wiring runs through somewhere. I don’t yet have the steering wheel on with the horn stuff in case I had this problem. AND I ask this specifically because I found that after doing all this my truck wouldn’t start-but I had a vague thought that perhaps the fuel tank selector switch needed to be plugged in to work and VOILA. So I know weird crap like that can keep random stuff from working. ANY HELP APPRECIATED.

 

Put the turn signal stalk in the middle. Do both brake lights work in the back when you step on the pedal? The rear turns and the rear brake lights are the same bulbs, the same wiring.

When you put the stalk left or right, do the external lights light up but do not blink? Check the front and the rear. Or are they just dark?

 

both brake lights work regardless of the runs being on or off, I have an aftermarket set of taillights I’ve never had an issue with that are bright and brighter when flashing but yeah brake lights function hazards all around function and everything

 

When the signal switch is moved left or right, are the lights dark(including the dash arrow lights) or are they on solid? If they are on solid, the turnsignal switch is working, there is something wrong with the flasher. If the lights are dark, then the wire from the flasher to the turn switch may have a break in it.

Another test; Turn the signal left, then hit the brake. Does your right rear bulb only light? And then move the lever to the right and then hit the brake again. Does the right light go out and the left light light up when the brake is pushed? If this works, then that is more confirmation the turn switch is working, and you are missing the flasher power.

 

Attached is a 1991 diagram. It looks the same as the 1986 below. I inserted the 1986 diagram because it shows the complication inside the turn switch and how it works.

 

So here’s where I’m at with this. I had found this diagram a few days ago and also the one where you can test the switch by ohming it out to make sure it is functioning properly everything ohms out on this new switch to within 10 ohms, the old switch has multiple kohm readings and they vary widely from the hazard reading for it and the turn readings. So I’m pretty confident that it was pretty bad(I even had like 6 Mohms on the left turn reading I believe).

As far as this diagram goes, I get 14 odd volts from the fuse to the flasher, then from the flasher (I’ve literally pulled the fuse block down to varify it’s coming from the back of the fuse) to the connector without being plugged in up to the pin, then I plug it in and still have 13.7-14 volts once I get through the connector up to where the light blue wire comes to the hazard landing. I can verify by taking voltage readings that when I change the hazard switch state from off to on that I lose the voltage coming in that was reading straight through up to even the turn signal cam. So I’m pretty confident all of that is functioning properly.

The issue is, when I go to turn the switch left or right, I drop all my voltage down to like .7 volts. I’m about to go see what I read on the hazard flasher wire when I engage it just to get an idea of what I should be reading, but like I said, why the heck do all my flashers work if my turn signals don’t??? It almost can’t be a bulb or anything to do with that stuff upfront? Right?

 

So as seen above I tried everything at troubleshot my little heart out trying to understand what was going on, I went out to test the voltage on my hazard side when that was engaged because when I turned my turn signal side on I dropped voltage and it just sat there. But the hazard side worked completely fine. Well, I had already tried putting that new flasher on the hazard side to verify that it worked, what I hadn’t done was say screw it and throw the hazard flasher on the turn signal side- cause why would I? I had a new one that I verified worked. Well, I threw that oem green flasher from the hazard side in and boom, turn signals work again, hale-frickin-luya. Just swapped that new flasher into the turn signal side and now everything works as intended.