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Installing LMC's Universal blinker 34-4900, 7 wire setup. I studied the tech tip here, the wiring diagram supplied by LMC with the blinker mech, and a wiring diagram of how the truck was originally set up to help me figure out what goes where. Hooked it all up and got nothin'. I had my wife hit the switch and the brake with the truck on and got an interesting symptom.

With the hazards on AND the brake depressed the Flasher ticks and my front right blinker (or front passengers side) was lit up solid. No other light on or blinking other than the red indicator flashing on the switch itself. Thats the most I can get out of it so far.

At least I know it has power and the grounds are good. but beyond that I'm stumped.

I think I found the plug that is directly before the directional switch's original location (in pic 2) and that's what I hooked the wires for the lights up to.

Here's the diagram LMC provided (pic 1) the diagram of my trucks wiring originally (pic 2) and the way I wired the blinker up (pic 3)

EDIT: truck wires on left, signal switch wires on right.

Light Blue/Yellow - left front
Dark Blue/Green - right front
Pink/Orange - left rear
Violet/Brown - right rear
Orange/Red - stop light switch
Black - flasher L position
Blue - flasher P position
Red - flasher X position

thank you all in advance.

Quadruple check your grounds.

I was planning on checking the grounds at tail light tomorrow. They just stopped lighting up when the headlight switch is pulled but the license plate light is working as well as the parking lights. I will add the other grounds to the list for tomorrow. Also I just thought maybe I switched violet and dark blue around, they are almost the same color after all this time. maybe why it only kinda works with the brake pedal depressed?

Went through the grounds, I cleaned the one at the switch, both tail lights and both front blinkers. I got my regular tail lights back They needed the braided ground cable from frame to bed to be replaced.

but I still have same problem with the blinkers >.<

I flipped around the violet and dark blue wires but it remained the same so I put them back.

It is power from ignition to brake light switch correct?

These type of problems are hard to determine from a distance, the cause could be a number of things. Here is where I would start:
Because:
1. Nothing works when you try the turn signals alone
2. You do get the blinker "ticking" and a bulb lit when you press the brake switch

I might check the wiring to the blinker, especially the "X" terminal. It should have battery voltage on it. It seems it may not. It is the source voltage for the turn signal device.
The brake switch is the other source of battery voltage to the device when depressed (physically not emotionally). It may be, that when the battery voltage from the brake switch is available, it activates some parts of the circuitry. And that is what you see as a clue.

I have attached a PDF of the actual device from the manufacturer's website, so it should be clean. It is much easier to diagnose once you see how the device is
internally wired.
don

Thank you, I was thinking it may be something at the flasher, the PDF should help quite a bit. I will clean the contacts at the fuse block and confirm that I'm getting 12v out of the connection. I will post the results.

confirmed 12v at X terminal of flasher no change

I followed the wires from each light all the way up and cleaned all the connections and confirmed my wiring. I had the rear blinkers wired backwards but upon putting it right I either lost a ground or blew a fuse. no more tail lights again but this time the dome light also stopped working which is new.

I figured I should replace all of my ground straps but none of the parts stores in town had any grounding straps so I ordered some from amazon. My fuse block is pretty tore back as well, so I will inspect fuses and clean off all the tabs tomorrow.

is there anything else I should check or look for that anyone can think of?

It's not shown on the wiring diagram, but the signal switch needs to be grounded. I suppose that it's expected that tightening the worm clamp will ground the switch to the steering column. That doesn't always work. I wrapped my column in thin rubber to preserve the paint so I had no ground and I had problems. Running a ground wire from the clamp to a good ground under the dash was the solution.

I unscrewed 1 of the screw that hold the switch's housing together and added a ground wire from there to a known working ground. I did paint the housing that the worm clamp is around and tomorrow I will grind it down to steel at the bottom am make sure it's making good contact.

Another thing I'm considering is a bad flasher unit. I have another from the old mechanism I will try out tomorrow. only thing is the old one is 2 post and the new is 3 I figure the only difference is the P (pilot) post do I just put it to L as well? I think I read somewhere on here to put both L & P to L if there is only 2 posts, please correct me if I'm wrong.

So far I've been adding redundant grounds to any problem area. Can't have too many.

EDIT: Sorry if I'm not making much sense I've been under the truck in the dirt removing superfluous wires from long forgotten lights/trailer hook-ups.

Keep at it... the problem will certainly not be the last thing you find!

Okay, I confirmed grounds at switch and the housing for each light, all is good there. My tail lights are back again, it was the fuse block not getting a good connection at the fuse itself, a little sanding on the tabs and all is well on that front. once I had power at the block (v12.32) I hooked up the 3 prong flasher unit and it blew the inline fuse (15a) I replaced it and all was the same. I then used the 2 prong flasher unit I had laying around. It was closer to right but not quite there.

2 prong - ticks without having to depress the brake pedal in hazard and when in the right turn position. also the pilot is lit consistently unless flasher is ticking in hazard or right position. only front right light is lighting up, but with the 2 prong flasher it actually flashes instead of being solid. Left turn position gives me nothing. all lights work on the dim filament.

both power sources (from the fuse block to flasher (v12.32) and at brake switch (v12.31) ), are working

pressing the brake gives no lights but the switch is functioning properly, and has power supplied.

I found some problems, and made some progress.

the 2 flasher units I have (1 from LMC (3 prong) that came with the blinker mech and the other (2 prong) was rolling around in the truck when I got it. the 3 prong doen't work at all from what I can tell. Power just stops at the X terminal. The old 2 prong unit works-ish.

The plug that I wired my switch to was in worse shape that previously thought, I cleaned the contacts and pushed the wires in the best they could go and with the 2 prong flasher almost everything worked! Brake lights functioned properly and blinkers/hazards worked with the exception of the front left blinker, but I'm pretty sure it's the plug. I will bypass it tomorrow or maybe replace it if I see a cheap plug available.

second issue is that the 2 prong flasher works fine for about a minute then it starts rapid blinking and stopping for a few seconds before coming back, it also gets really F'ing hot after 45-60 seconds. and leaves pilot lit constantly unless blinking, I figured I just leave the pilot wire off would that work or does it need o be a complete circuit?

As far as flashers go should I buy a 2 prong or 3 prong?

Bought new 3 prong flasher, everything works fine now. thank you guys