1/2 ton 4X4 GMC Suburban. Battery is over 13volts. No headlights, dash lights, gauges and doesn't attempt to start. I connected jumper cables and the same thing....Nothing. I don't know where to start.

 

Check your ground wire.

 

Will do in the daylight. Thanks

 

Disconnected ground wire from battery and block. Connections were clean and tight. Reconnected still Nada

 

Do you have a fuse/relay panel under the hood?

 

Trace the battery + cable, there probably is an inline fuse.

 

I disconnected the battery and then connected jumper cables from another vehicle. It started up and I reconnected the battery cable and disconnected the jumper cables and it continued to run.
Let it run for a few minutes and it seems happy now. Pretty well baffled at what fixed it.