I have a 2011 lariat supercab 4x4
6.7 automatic. Dleted and SCT x4 tuner
Starting yesterday afternoon the truck has refused to start.
I get a single click from passenger fuse box then nothing.
Once in awhile the truck will start for about 15-30 seconds then shut down
Then just a click
Batteries are only a year old tested good.
Starter was tested good and I jumped it with a screwdriver once reinstalled and it will spin the engine.
Dash lights up with “service advance track” and “trailer brake module fault”.
My obd2 shows no codes but my buddy’s scanner popped up 1 code
P2531
The truck has 160k and has NEVER given me any problems before this.
Any help would be appreciated!

 

check the wiring for the ignition switch. Check connectors under the dash

 

So you described exactly to a T what is going on with mine. I've tried so many things. Tried wiggle test on wires under steering wheel with no avail and checked trailer plug for corrosion. Tested batteries, alternator, voltage drop between the 3 for wire breaks, tested every fuse and relay, tested grounds for engine, frame, alternator, and body, and new TBM. Had random codes pop up since with other modules on my obd 2 reader but after resetting computer the only code that keeps coming back is TBMF. This so far is where I'm at. I have the steering wheel apart and I'm now thinking it is the ignition switch. Truck has progressively stalled more while driving and has started less and less. When I say stall I mean while I'm on the highway stall truck turns itself off with no warning and the TBMF warning pops up. I incorrectly thought that if I unplugged the module the truck would start and then run. Which I did and thought that was the work around. Then once I literally plugged it in to get it back to running and then once it stalled I unplugged the module to get it back running. I thought for sure it would be the module. Nope, What I've noticed now is when I put key in ignition, the plug wires will come on and that's when I know truck will start. I wish I was paying more attention to that earlier to see if was happening then too. I hope it's just the ignition switch...idk what else to do. Did you get yours running? If so what did you do?

 

Ok so I replaced my ignition switch today...$25 dollar part. So far so good but I don't want to celebrate too early. No trailer brake module fault no service advance track no random stalling and I drove 25 miles without issue fingers crossed. I immediately noticed the key was a much firmer fit and the glow plug light came on when in the run position. I've cycled on and off probably 20 times today. If you were like me and thought that it wasn't related welp it is. Even, so I'm skeptical. One thing I noticed too was when I had no crank no start there were fuses on the sidekick panel that I previously tested good for continuity but had no power to them when I light probed them, they were 22-27 and 33-37 I think...it was seemingly a block of them no power. When I back probed the old ignition switch I was getting power from all wires depending on which position it was in of course (used my light tester probably should have used my multimeter)...but I'm not a mechanic I was just handy and desperate out of necessity to get it running because it was going to be weeks before someone was going to look at it and after 2 shops looked at it and had no answers I became more desperate. Also, some things I learned along the way that I will do in the future that yall should consider too.
1.) go to ebay and get a spare key, have it cut to match yours and then you can look up video on youtube on how to program it as long as you have your working master key.
2.) make sure all grounds are good and add ground from frame to body on both sides and on front and back of transmission (heard it could be a huge problem down the road)
3.) replace glow plugs if you still have originals (can break off and cause catastrophic failure)
I'm sure most of you already knew these things but I figured if one person reads this and it helps them, then that is a win.