LBZ: No Crank/No Start

[duramaxman2002]

nuetral safety switch

dont listen to these rookies. classic neutral safety switch crap. wont crank shift prindle not lite or confused. moisture on switch. snow rain doesnt matter. i have been through 3 in 140000 miles. replace but use silicone to protect from moisture. your dealer should does this free of charge. 1st generation duramax

 

[duramaxman2002]

if i wont start but powers up. shift to neutral and then start should fire right up and thats how you know its the switch. its designed to stop you from starting vehicle in gear. but neutral is not a gear. good luck.

 

[JoshH]

dont listen to these rookies. classic neutral safety switch crap. wont crank shift prindle not lite or confused. moisture on switch. snow rain doesnt matter. i have been through 3 in 140000 miles. replace but use silicone to protect from moisture. your dealer should does this free of charge. 1st generation duramax

I'm not sure what to say in response to this post. For starters, this thread is nearly two years old, and the guy who started it fixed his truck with the information in this thread. Now you revive it to tell him the info that he used to fix his truck is wrong? Amazing.

 

[duramaxman2002]

info

need more info to help ya. any key power ?. if so shift to neutral and try to start. are you out of fuel and the step motor bad (fuel gauge) did the fuel separate due to temp. bad fuel filter. i know this it aint the computer or transmission its why you paid all the money. they are bullet proof. running any programmers or tuners if so thats your problem. more info and i can help. duramaxman2002 02 3500 dually ppe flasher(which i dont use anymore) 140000 6 inch magna flow.

 

[JoshH]

 

[cketcc]

help

not to surehow to post my own but my truck is doing same thing we changed starter check wiring harnes all fuses and re did the ignition.. i have all my dash lights on.. 2 things it will do 1 when i turn the key it makes no noise wont turn over no clicking NOTHING... or 2 when i turn it on it just keeps trying to turn over but i get NOTHING... any one have any ideanwhat to do

 

[Chad W]

need more info to help ya. any key power ?. if so shift to neutral and try to start. are you out of fuel and the step motor bad (fuel gauge) did the fuel separate due to temp. bad fuel filter. i know this it aint the computer or transmission its why you paid all the money. they are bullet proof. running any programmers or tuners if so thats your problem. more info and i can help. duramaxman2002 02 3500 dually ppe flasher(which i dont use anymore) 140000 6 inch magna flow.

Wow. Old Thread but a new laugh for me. Too much exahust inhaled from that 6" magna flow.

 

[DMAXchris]

Look like this? If so, yes.

Thank you so much for the photos and info! Ive been fighting this for days. Went out and spliced the wire and she fired right up!

 

[minisub]

:thumb:

8 years later, the fix that keeps on giving...:roflmao:

 

[coachmike]

Had the same problem on 2006, All the dash lights, fan, and all other lights worked just would not crank! thanks to this forum I found the wires had rubed thru. I found a Blue wire and the Grey wire were broken. Thanks for the info, It saved me alot of time and Money:thumb:

 

[01 chevylover]

I know this an old post but I am haveing the exact same problem and I am hoping it's a worn down wire does anyone have good pictures of the wire and where is it's normally getting worn thru so I have a starting point on where to look

 

[Dozerboy]

Can you not see the pictures that have been posted here already? The ecm is located on the driver side fender down by the frame and steering shaft.

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[minisub]

Exactly. Post 17 and again in 28.

 

[Hambone]

Bringing this back again!
I was so hopeful that it was the fender wire but it’s not....
Going off the wire diagram I now need to see if I’m getting voltage to the nsbu and also the ecm because apparently they split between those two before going to the relay
My question is shouldn’t the truck start when I’m using my dummy solenoid and forcing the voltage through and actually getting the truck to crank?
I need to hook up the computer and seen what the ecm is commanding for fuel I guess when I do that

 

[Hambone]

Figured out what it was...
Was checking ground in Tcm hoping it was something simply and decided to check ground in the ecm once everything checked out good but when we unplugged the ecm we heard what sounded like marbles inside it so we popped it open and found this
Also makes sense why I wasn’t able to connect fully to the ecm but had some monitoring abilities

What are my options now?
Do any vendors sell Ecm’s?
eBay and reflash it? Where do I get a stock 07 file?
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[Meisner83]

The thread that keeps on giving

So I surfed quite a few Duramax forums when dealing with the no crank/no start issue. This was issue on my 09' LMM.

 

[DixonM]

I had this issue recently turned out to be the ignition relay under the hood. The truck would shut down while driving and sometimes when you try and start the truck it would not spin over and had a service brakes scroll on the dash display it was intermitting but lasted one day long enough to find the issue. Damn near traded it in for a $10 part.

 

[nathanowensby11]

having same problem on my 2004 lb7 no crank no start just died on me one day and now won't start i have loom apart can't seem to find the problem please helppp truck has been down for a month now.

 

[juddski88]

having same problem on my 2004 lb7 no crank no start just died on me one day and now won't start i have loom apart can't seem to find the problem please helppp truck has been down for a month now.

Time to find a good technician to bring it to

 

[2004LB7]

having same problem on my 2004 lb7 no crank no start just died on me one day and now won't start i have loom apart can't seem to find the problem please helppp truck has been down for a month now.

Log the fuel pressure while cranking. Post results here