Wires help.

I’ve got an 08 regular cab. I wanna know what the purpose of these four wires are, and if I can utilize them.

 

Without knowing wire colors and being able to see the connector shapes better I'm not 100% but I'm pretty sure.

 

Not counting parking break, what do the three do?

 

J2 and J3 are junction connectors for the dash illumination Power and Ground circuits.

Z1 would be the Towing Converter for trailer lights if you had the Towing Package.

Not sure what your wanting to do?

 

I was just curious. What would I plug into the trailer one? I have a hitch with wiring. Also what do the unused dash wires do if my dash is already properly lit up?

 

The Towing Converter Relay is only equipped on trucks with the V6 Tow Package, it controls the trailer Stop/Turn Lights. Trucks without the towing package typically don't have all the necessary wiring to utilize it.

J2 and J3 aren't unused, they are called junction connectors. Essentially it's a connector that is plugged into a comb that bridges the terminals.
The dots and lines represent which terminals are bridged.



This is J12 but J2 and J3 would be plugged in the same way just different wire colors.

 

This is how they appear on a wiring diagram.

 

Thank you for your help.