LMM: another wont crank

[6dot6]

out of no where when i went to start the truck it didnt do squat. i did hear faint clicking. tested everything i could,i was getting juice. next day went back to truck and it started like nothing happened. i load tested each battery and they were "ok". little weak but usable. ended up spending 400 on diehards anyway. so couple weeks later, no start again.
whats happening is it does not want to crank. also another thing when this occurs is the airdog wont come on. see below:

symptoms:
no airdog on key hot (fused in aux hvac-ign)
no crank (clicks and hisses)

all other fuses seem to work when this happens
all lights and such work
does not start with remote start either

so ive got some sorta problem. what im curious is what type of signals are getting sent out from the ignition? are there multiple signals? wondering if just some or one of the signals supposed to be turning on and sending out are not doing their job! has to be a short somewhere.

so as soon as a buddy pulls up with a snap on scan tool, what do you think happens? freaking starts!!!!!! so now im not sure if i pulled out the cts earlier in anticipation of him using the port, or if i pulled it out just before i tried to start it. so now i couldnt really check to see what was or wasnt getting power. now im scared to go on the kentucky trip. im nervous to go anywhere now!

im going to dig under the fuse block and see if anythings corroded under there. also ill clean up the connections at the distribution block. other than that im freakin out of ideas.

when it happens i can just feel the run crank jcase fuse clicking. how the hell do all the fuses work cept the hvac aux-ign(possibly more but havent noticed)

 

[bullfrogjohnson]

Sounds like the ignition switch

 

[TLyons90]

^x2 or a short somewhere in the ignition system.

 

[6dot6]

im thinkin i should just let a dealer do it. my buddy has the scan tool but im not sure how savvy he is with it. if its gonna be more than a million bucks from the dealer i may try it myself first.

so this is the general consensus? faulty ignition? i sure hope so, i hate eletrical gremlins.

 

[6dot6]

oh truck has 35k on the clock. darn shame. was embarrasing when the guy in his powerstroke parked next to me started his truck up no prob and then had the audacity to ask if i needed jumper cable. the nerve of that nice gentleman!

 

[NC-smokinlmm]

Sounds like the ignition switch

X3...

 

[bullfrogjohnson]

IMHO.... the ignition is the only thing it could be. If the airdog is run on a key on power and when the truck won't start the airdog is not running, the ignition switch is stuck in the off position.

 

[6dot6]

yeah but strange thing is it will make the run crank jcase relay click. its freaking strange.

 

[Daddy Big Dawg]

I know up herein our lovely salty air we've had a lot of issues with loose terminals/corrosion/ etc... in that large harness that's located on the drivers side by the upper rad hose

 

[6dot6]

im searching the google and finding lmm have a lot of no start issues. ive looked at connections. fuse block does get juice. just not ones i need to start.

while i had the prob i noticed glow plug was out too i believe. i dont think check engine light was on. i was getting service 4wd i think or service transfer or some crap. you would think i would freaking remember. i dont recall if security light was on or not. wish i did. so pissed at the time i didnt freakin pay attention like i should have.

 

[6dot6]

going to use my other key from now on and see what happens.

 

[RPM Motorsports]

Clean the small grounds on the front sides of the block. Follow the small starter wire back to them. The front one on the pass side will give a no crank if connection is bad/dirty.