I just purchased a 2005 GMC 4500. It was a repo deal and needs a few things. It has air suspension in the rear, an aftermarket deal I am sure. I got the compressor that controls it working. Just a simple electrical short. The bags are regulated at 35psi, the compressor fills the storage tank to 145psi. All good there. Everything checks out, and I am tickled that I was able to fix it. Now there is another tank and compressor on the other side (drivers). It controls the exhaust brake and provides air to the seats. I believe this tank and compressor as well as the exhaust brake are factory by judging from the wiring harness. The seats I am not sure. The truck was done by Dixie Custom Trucks who I called and is out of business.
The seats do not work. When I first looked into it they were unhooked from the tank. I plugged the hose back in and figure that would fix it but no go. So I unhooked them from the tank and had a person blow air into the line from a shop compressor while I operated the seat. They worked then. I thought the exhaust brake worked but now I am not sure. When the switch is flipped it does shift down and slows faster. Also a green light comes on with the exhaust brake "picture". I am beginning to think that the maybe that switch also tells the tranny to downshift sooner? Maybe? And the Jake is not working. It doesn't feel quite like the "big" trucks with the brake on that I have ridden in, however I have never drove one so. My guess now is the seat hose came undone and burned out the compressor motor?
If this is the case could I save a few dollars and hook the Jake and the seats to the other aftermarket tank? Or would 145psi be too much? If it is too much do they make a regulator that I could use.
My next step is to hot wire the suspect motor and see if it runs. If the stock compressor motor is kaput and I have to replace it where do I get parts?
Thanks, if any of that needs clarification please ask!!
As a general rule, people are nuts!