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my2003 sierra5.3ltr wont start checked battery and connections good. checked fuses seem good but i noticed that the steering wheel is not locking could this have somthing to do with this?I can hear fuel pump and all lights and every thing work but nothing happens when I turn the key please help dont know where to go from hear  

a few things...

does the engine crank when you turn the key to the run position????

you could have a problem with the security system that is embedded in the ignition switch...

warning.. it takes a set of TINY external torx sockets to remove the column cover.. and to remove the turn signal and ignition switch ... its probably an E-4 or E-5 socket.

when you turn the key on...  does the security light on the dash board stay on???????  if the system is working.. the light should come on and then go off..  if the security system have been tripped.. it will lock you out for 4 minutes ...   you can.. with a watch.. turn the key on for 10 minutes and wait...   watching the security light..   when it blinks out.. you should be able to start the engine...  at least ONCE...  

no it doesnt crank and the security light doesnt stay on it comes on and goes back out im thinking because .
the steeringwheel isnt locking this might have something to do with it it never give me any warning worked perfect until yesterday any help would be greatly appreciated  

no cranking is a slightly different situation...

this involves a LOT more stuff...

a few things first...  set the parking brake...    turn the key on..  with your foot on the main brake pedal.. pull the gear shift to neutral...   see if it will start there....

if it does.. then it might be the transmission manual lever position sensor..  thats a quick test..

there could be a lot more things...

lets look at the diagram.,...



you are going to want to print this diagram..

when you turn the key... the ignition switch sends power to the engine computer.. the engine computer decides if everything is ready to crank the engine..      

there is a starter relay in the fuse box under the hood above the left front tire..  that could be bad.. the 40 amp fuse in cavity A could be blown...

the battery cables could be dirty... on either end where they attach to the engine block or at the starter its self..

the starter motor could be bad...

the starter relay in the box under the hood looks like this..



normally cost under 15 bucks...

if you can identify which one of the relays is the starter relay...  you could either swap it with another or unplug it.. take a pair of small screw drivers and pry its cover from the base...   you could then either clean the contacts like i ***  or just plug it back in without the cover..   squeeze the top plate.. and see if the engine cranks..   if the starter actually works.. this bypasses the entire computer system to crank the engine..

 

oh... when you look at the bottom of the relay...



pins 85 and 86 are the coil windings...

pins 30 and 87A/ actually 87 on this relay are the starter power contacts..

when you squeeze the movable contact down to contact the fixed contact.. you send power from 87 to 30...  

thanks waynep for all your help.