Is there a way to manually turn on and off the Air Supply Unit manually on the compressor itself? I do not have the remote...

 

NO, why do you ask, what is yours doing or not doing?

 

What remote do you not have? There's a switch on the dash to raise the rear end off road but other than that the system is automatic.

 

There is supposed to be a remote control you can have to control the air suspension, at least according to the owners manual.

 

That is an option and I think you need to get the dealer to program it for you.
It does exactly what the dash button does, raises the vehicle 3", only remotely.

 

Wrong!!!!!!!!!!!!!!!!!
It doesn't raise the suspension, it drops the suspension making it easier to load a trailor then brings it back up to normal.

 

Either way I have never heard mention of a remote for a D2. Learn something new every day. Mike's explanation does make a little more sense. It seems to be more beneficial to lower the suspension from outside than to raise it. I have never run into a situation trying to load something in the back or hook up a trailer that made me think I wish the back of the truck was higher.

 

It does lower the suspension. I have priced them out and it's $125 from my dealer JUST FOR THE PROGRAMMING. The fob with the remote is another $150. A little too steep for me.