Short in BAT Circuit, Lighting Gremlins

[punkrex]

Okay so I have a few electrical issues that I need to get sorted, they may or may not be related so I figured its best to state everything. Truck is 1999 K1500 with auto, about 250,000 miles on the odometer.  

 

Back up lights do not work, at all.

Parasitic draw in the BAT (50A circuit)- don't know where it goes, I think the ignition switch but the diagrams I've found aren't so good.

Cargo light doesn't get power when switched on (even with cab light on)

Sometimes a tail light will go out and then come back on

Sometimes the blinker lights don't work

Sometimes the dash light for the blinkers stops illuminating but I can hear the switch ticking.

I have lost headlights while driving (scary when doing 65 in the snow over a mountain pass). they come back on after cycling the hazards for a spell (coincidence?)

 

I suspect I've got a chaffed wire bundle for the lighting circuit but I don't really know where to start looking without tearing the dash apart.

 

 

 

 

[bronyaur]

Check all your grounds and your main ground strap.  Grounds are famous for gremlins.  That's where I would start.

 

As for your cargo box light, mine only comes on when the switch is on and driver door is open.

[punkrex]

Any help on the open BAT circuit is appreciated, pretty sure it provides constant power to the lighting circuit but I don't have a draw on the lighting fuse located on the driver side dash, where else should I look?

 

I recently replaced the engine and went through the grounds from the bat to the block, bat to fender, and strap to frame and firewall. I think grounds are good.