04 2500HD 8.1 - Can someone identify these 2 plugs near the fuse box?

[ruggiero06]

Here are the 2 plugs I need to be identified

[davester]

That plug near the base of the fuse box (top photo) looks like the plug for the 4wd system (the 4wd harness plugs into that).  It's open/unused if your truck isn't 4wd.

Edited January 7, 2019 by davester

[ruggiero06]

The bottom picture with brown, black, gray wires is connector C153, black, 3 wires. This connector contains 4 Wheel Drive wires, for front axle switch, and LOW Range Signal

 

Anyone know what the top plug is?