Well, since pulling the rear bulbs gives you a hard failure..... Yank the bulbs, and see what's missing. Fuel, Spark, or both..... I would suspect fuel...... Might wanna check the ground for the fuel pump... It's the only critical thing on that rear harness.

 

i dunno maybe this narrows it down??

i pulled out the Head light switch un hooked the 2 connectors.. no change..

then i unscrewed the multiunction switch for the Hazard wipers turn signal
kills the engine... engine wont fire if unplugged.. plug the mulitfunction switch back in.. i can fire it back up

does that say anything? do i need to try to trace the fuel pump ground
i dunno how to test for spark by myself cnt hold the spark plug and i still cant get computer odb reader to read the truck and i dunno if the hand held innova tells me spark.. its those ones tht gives codes reads some data.. and if you pay 100 bucks you can get it to read abs... but ill try to see if i get fuel pressure i got that tool that will tell me if the pump is working

but ya i pull that plug out for the hazard high beam etc it shuts the truck off

 

does it help maybe where i can localize search for something faulty... as it cant be the wiring to back or can it still..

 

See what's missing with the switch unplugged. Verify you get power to the ASD, and fuel pump relays. Does the pump even prime with the switch disconnected? Also verify the control side circuits for the relays.

 

so more test.. what is the ASD? and what is the control side circuit relays

so my fuel tester pressure broken its missing the insert to press the tit...
so i had to use screw driver..
i turnned key 3 times i heard the pump i guess wit the mulit function plugged in.. when i use screw driver on the fuel rail port.. i get litte pressure
when i turned key 3 times with the multifunction not plugged in.. and when i used screwed driver on the fuel rail port no pressure
then i re tried again pluged multifunction it.. i get a little pressure.. fuel shot ul 1 inch not like on my 2004 cav shoots like 2 3 feet..

also when i do the 3 keys.. the Odometer says "P Done" i guess that means pressure done.. i dunno..

so im guessing the fuel pump isnt working when the mulitifunction isnt plugged in but i do hear the fuel realy kicking in i just wish one of you guys was here ..so i could hear the tank while you turn the key.. single life sucks during pandemic times no one willing to help especially when you live in rural country..
i guess you mean check wheats all missing like head lights tail lights..
ill try that see ... but this getting frustrating i tell ya..

 

P Done in the Odo means no stored codes.

If you aren't getting fuel pressure with the switch unplugged, that is gonna be a problem. In the Power Distribution Center, under the hood, right behind the battery, there are a whole buncha relays and fuses. The map for them should be on the underside of the cover. The ASD relay is the Auto Shutdown Relay. It supplies power to the coil, and injectors. (probably some other stuff as well....) It will get power for about three seconds at initial key on, then shut off again, it won't re-engage until the PCM seems the engine turning. (signal from crank, or cam sensor.) Fuel pump relay is in there as well, its only job is to supply power to the fuel pump. It will also come on for three seconds at initial key on, trip out, and then be re-engaged when the PCM sees the engine turning. (same conditions as ASD.)

They are five pin relays, but only four of them matter. (pins are labeled on the underside of most relays.) Pin 30 is going to be the main power feed for whatever the relay is actually supposed to power. Pin 87 is the other side of that circuit, and goes out to whatever the relay is supposed to power. (in the case of the fuel pump relay, that would be the fuel pump itself.) Pin 85 should be hot with ignition on, (I think, haven't check the diagrams for your specific truck.....) This is the control side of the relay. What the PCM uses to turn the relay on and off. Pin 86 is the ground side, and is controlled by the PCM. If the PCM wants the relay on, it will supply the ground on pin 86, thus engaging the relay. (assuming everything is working as it should. )

When you turn the key on, you *should* be able to hear the fuel pump run for a few seconds. If you don't hear it, put your finger on the fuel pump relay, and try again, you should be able to feel the relay click. (try the ASD relay as well, gives you an idea of what it feels like.) Gonna need a second warm body for that particular test though, unless you have arms like an orangutan. I have used my grandkids as the second warm body..... They can turn a key.

 

ok so the ASD is the Auto ShutDown relay then?

well i can try and feel for it all.. ugh i wish i had oger arms lol.. does my dog count as to turning the key.. thats all i got right now.. lol send your grandkids here i need to borrow there turning the key skills.. but ill see what i can do.. ill check the replays etc.

 

You might be able to teach your dog to do it........ I have had no success with that with mine though. They just look at me funny while sitting in the drivers seat, and are probably wondering why I am not taking them for a ride.....

Where ya at? Shipping for grandkids might be a tad expensive....

 

ontario canada.. well sending grandkids you get kids free so the shipping is your payment to have kid free.. lol

so i tested.. what i did was pulled all the relays in the fuse panel,, also pulled out hte bcm so they dam key stops binging at me,
had the mulit function swith out
turned key.. to on.. i heard the ASD relay click in.. it also worked with the multifunction plugged in
so then i plugged in the Fuel pump relay in
mulitifunction switch out.. turned key i heard relay click..
multifuction switch in ... turned key i heard the relay click.. and then i heard a thud in back.. so i didnt heard it running just a thud. so i guess when stopped ..
had to pull all relays too much noise under the hood lol.. i guess the computer also clicks as it was giving me hastle to listen.. havent tested power relays.. my test probe wire broke off a the probe
dam junk mulitmeters lol

 

i neeed to teach my dog to drive.. that way i can sit in the pass side lol