All interior lights not working / 4wd switch not lighting up or engaging!!
 

Ok, so the problem I' am getting is I installed a new heater core yesterday!!! First of all I'd like to say...what a lot of work!!! So I took out all the dash carefully, disconnected everything, a whole bunch of hours later, heater core installed! I put every thing back together exactly how it was, added new coolant, started it up, good to go!!! Inspected everything...turns out i lost all my dome lights including vanity mirror, and two little lights on rear-view! Also my 4wd lights were not lite up & transfer case will not engage! checked fuses inside cab, only one blown was cigarette lighter! I have been frustrated ever since. Is it possible that I never connected something to or from the dash? The connection to the 4wd switch is plugged it perfect on dash) is there another connection i missed plugging in to send power to it? Dome lights too? I noticed that on the drivers side floor, right below foot brake & running from the same wiring harness as the code reader sensor connection, that there were two connections not plugged in anywhere? not sure if I disconnectioned them, pretty sure I didn't! Could they be for something else, or for some aftermarket part??? really need help?? roads are like the glass this winter!!!

Lets start with what you are working on..

I can take a wild guess that you are working on a 2nd gen with the NV236 (4-button switch in the dash with auto4wd) just by looking at the wiring schematics.

The courtesy lights and the TCCM are both powered through the CTSY LP fuse in the IP fuse box. It will be a 10A fuse in the 2nd row from the top, 3rd from the left.

If you don't have factory remote door locks one of those connectors would be for that.

Problem solved!
 

Thanks for the quick responses! turns out it was the CTSY LP fuse!!!
You peeps are awesome!!