You have a wiring issue for the rear lights. Go get the fsm and check the grounds and all the wiring.

 

ah ok ill take a look..
and is there 1 section id look for just the rear lights grounds since its impossible to search every single wire..

any spot i localize that cant be any other area..
but ill look tomorow for the FSM

 

i having a hard time understanding the FSM
i on page 974 (8w-51-5)

is G100 the ground wire as i dont see the fancing upside down symbol to represent Ground
trying to find any grounds
as i goto the 8w-15-7 page ground page and i guess thats all the ground wires all joinned together

i probably gotta re go over things serveral times i have dislexia so it takes me a bit longer to figure things out

and where is joint connector 3 located.. and what connector is it called at the drivers wheel fender big plug what one is that called.. is there a list of alll the wires and where they all goto

 

You can check the grounds but the lights should have nothing to do with the ignition. You have something really screwy going on there. I would remove all the lights in the rear then see why you don't have such as power to the asd relay etc not letting the engine to run.

 

ah ok ill try tommorow best i can.. go figure right.. like what the heck.. Covid19 has infected my truck. and trying to figure this manual and find these connectors

wish there was like some big corosion then you can saw ah ha there it is right there... but so far havent found anything bad that causing it
i asked at Canadian tire a mechanic.. he said could be BCM or wiring well that narrows it down lol

 

I think something is back feeding the circuit.

 

I can try and explain the manual if you want. But it would be easier over the phone.

 

unfortunately i broke my phone over a month ago.. screen broken havent found a replacement.. as i was going to make videos of what i dealing with .. as then you can see what i dealing with..
as im sure sometimes this too hard to believe.. that the tail lights if not plugged in wont let the engine run..
and who knows if mice got in and chewed something... and then i was thinking from the fsm its the multifunction switch.. but i replaced it already as the wiper motor wasnt working turned out it was the switch ..
wonder if i unhook that switch then no lights maybe works.. it does get frustrating

but ya i have no phone to hear ya explain it.. just a covid year...

 

I am REAL curious why pulling a brake light kills the engine. They are two entirely different harnesses, and there is no overlap that I am aware of.

Somewhere in the truck, the wiring has been butchered. Time to start tracing circuits for the PCM/Engine.

 

i was thinking mice maybe.. it wasnt driven much during this pandemic times... i know it had this issue 2 months ago i thought was rain and wet wires.. the brake lights were on.. but once it was idling 30 min i figured dry up the wires.. the brake lights went out truck ran fine was able to drive it now.. its nothing and this issue

its like the brake lights are acting like a small engine when you short the spark plug to ground as your kill switch...
i dont even know where to look yet what about the wire harness going to the fender it goes to the back is that anything important? hmm ill keep trucking at it toda to try to find something