What is this switch for (Freightliner)?

Making a long story short - I quit my career at 48 years old, and now spent my first week on the road (day trips) - just loving it.

They kind of just threw me in a truck, and off I go. I have most everything figured out in the truck, except for a thing or 2.

It is a 1996 Freightliner with a short sleeper (sorry - don't know the model number yet).
Anyway, next to the ashtray and lighter, there is a switch next to the right window switch. It has a red label under it - says "auxiliary" on & off. When it is on, there is an ever so faint beeping coming from the dash. What does this switch do?
Also, I've never had a sleeper truck before - trying to figure out how the heat & a/c work. When the truck is running, does the heat and coolant automatically circulate to the sleeper unit? Do I just need to adjust the temp and fan speed from the back?
Or - does that red axillary switch have something do to with it?

Thanks - just getting the sleeper set up since I will likely be doing some overnight runs very soon.

Originally Posted by prosperity

Making a long story short - I quit my career at 48 years old, and now spent my first week on the road (day trips) - just loving it.

They kind of just threw me in a truck, and off I go. I have most everything figured out in the truck, except for a thing or 2.

It is a 1996 Freightliner with a short sleeper (sorry - don't know the model number yet).
Anyway, next to the ashtray and lighter, there is a switch next to the right window switch. It has a red label under it - says "auxiliary" on & off. When it is on, there is an ever so faint beeping coming from the dash. What does this switch do?
Also, I've never had a sleeper truck before - trying to figure out how the heat & a/c work. When the truck is running, does the heat and coolant automatically circulate to the sleeper unit? Do I just need to adjust the temp and fan speed from the back?
Or - does that red axillary switch have something do to with it?

Thanks - just getting the sleeper set up since I will likely be doing some overnight runs very soon.

The auxiliary switch I have not a clue on this unless it was used for a back up light, or maybe to turn something on for the trailor that was being pulled before you got it.
It should not have anything to do with the sleeper heat or A/C.

You might want to check under the hood on a freightliner you used to have to trun the water valves on and off in order to have heat or to have A/C. I am not sure on a 96 model.

As for using the controls in the sleeper........this depends on the driver. A small sleeper will heat or cool pretty fast depending on if it is working right also.
You will just have to get in it and play with it. I myself like it to be cold in the bunk when I drove OTR I could always sleep way better that way.
I would usually have the A/C on in the front and back, if working right you will not have to have them both running full force.
Heat is another situation as I liked it cool to sleep so I never had the heat on in the sleeper.