My First Project and GMC has me stumped

[whenindoubtuseahammer]

Good evening. I was lucky enough to get passed down to me a 2007 GMC LBZ that was my great uncle's. While the underside and rockers are more or less gone I feel like with time I can restore it to working order since it only has 110,000 miles and he put nearly every option he could get without getting the new body style since he did not trust DEF. So far I have done everything I can think of but when I put the key into the ignition nothing happens. I put 2 brand new batteries in it. Cleaned the terminals. Check all the fuses and relays and they all pass with my multimeter. I know I'm missing something that I just cant think of. The only odd thing is the OBD2 port works which makes me think its not the mega fuse. Any advice would be greatly appreciated. 

[davester]

are there any codes?

with lots of rust, perhaps disconnect/clean both sides of the connection/examine cable ends (the wires) for corrosion going into the sheath & replace if necessary/reconnect ALL the power AND ground cables between the battery, engine, frame, cab, fuse box and starter

charm.li (website) has a no-start diagnostic procedure you can work through to get it working.

[newdude]

11 hours ago, whenindoubtuseahammer said:

 So far I have done everything I can think of but when I put the key into the ignition nothing happens. I put 2 brand new batteries in it. Cleaned the terminals. Check all the fuses and relays and they all pass with my multimeter. I know I'm missing something that I just cant think of. The only odd thing is the OBD2 port works which makes me think its not the mega fuse. Any advice would be greatly appreciated. 

 

 

So when you put the key in and turn it on, do you have anything at all?  Radio?  Lights?  Or when you key it on its dead?  Or is everything working and it won't crank?