I've a '99 1500 w/5.2L and Auto. I put the key in the ignition and nothing comes on in ACC and nothing happens in Start. I have no interior (Dome or Instrument Cluster) or exterior lights working (Headlights). My battery has over 12v. I've checked all the fuses and relays, all good. I have no clue where to look to now. Maybe ignition switch, but highly unlikely since no Headlights. Please point me in the right direction...thanks...

 

Did you check things in the power distribution center under the hood, behind the battery? Sounds like a blown main fuse.

 

Yes I did. That is the part that I can't understand. All the fuses and relays in the PDC are good. I even have my own "test" relays without covers so I can manually make them operate.

 

Might check for lose grounds wire/cable's too...

 

Grab a multi-meter, and find out where you lose power. Given that EVERYTHING isn't working, shouldn't take long to find the right spot.

 

Remove battery terminals, clean, reinstall, and tighten. I had same problem. This fixed it for me.