2003 6.0L Silverado: 14K miles. two times now no starter or solenoid clicking when ignition key is turned. Dash lights and bells and other accessories come on fine. In both cases the truck sat outside for a week unused and a huge rain storm occurred the night before. In the the second case it started normally 2 times but failed while out on errands on the 3rd start that day. Hence, I am not sure the weather is related? Tried knocking the solenoid and starter...no luck ... only after about a hour or so trying the switch did it work... I'm on the forums now looking for diagnostic guidance. I plan on checking and cleaning the battery terminal connections (no apparent visible sign of problem now from looking at the terminals when connected), and will also check the wired connections but removing and checking the connections at the solenoid and starter. Any other ideas? thanks

 

Sounds like a faulty ignition switch.

 

Check the cable connection at the battery. A poor connection can act like that. Enough juice to run the accessories, but not enough to turn the starter.

 

Thanks folks. I'm going after the easy stuff first. I pulled the cables off the battery. No visible corrison or gunk. I did notice that when the snow plow installer (last year) had to connect a ground lead to the battery directly...he pulled the plastic grommet off the lead so a simply copper tab lead could rest atop the trucks ground lead at the battery. The holes of lead tabs may be a but bigger than the seating surface of the special bolt that screws in the delco side terminal battery. I probably will add a washer that makes this a little snugger. I also was able to easily pull a big lead off the starter solenoid. I did notice some minor greenish corrosion at the perimeter of the contacting surface...wire brushed it all to nice shiny condition...getting at those starter leads is ridiculous...shame on GM. Lets see if it fails again... Any other first try thoughts out there are appreciated>>>. thanks