[rheavn]

I misunderstood your post.  When you said the 12V pump does not supply air to the front slide seals, I thought you had eliminated the front seals from being supplied with air from the 12V air compressor.  If I understand you correctly you are saying that the 12V air pump is supposed to supply air to the front slide seals, but isn't.  

If the 12V air system leaks down below 60 psi when the 120V air compressor is shut off, then you have to look at a couple of possibilities.  When the main air system is above 60 psi, the 12V air system is joined with it. If the main air system has an air leak and leaks below 60 psi, then there is a check valve that is supposed to keep your 12V air system from leaking off.  If the check valve is stuck open then your 12V air system will leak down at the same rate as the main air system.  But in this case the 12V air compressor should keep the 12V air system between 40 & 60 psi unless there are leaks that it can not fill quick enough to keep up.  

Completely drain your air system with both air compressors off.  Turn on the 12V compressor & see if it can bring the system up to 60 psi.  This will tell you if your 12V air compressor is good. Verify that you have air in the 3 gallon air tank in the right rear wheel well.  If it does, then shut off the 12V air compressor and drain the system.  I would now put my leak down tool on the air line going to the front slide seal before the slide seal regulator.  Turn the 12V air compressor back on and see if it is supplying the slide seal with air.  If it does, then check which side is leaking.  If the slide seal regulator is not being supplied air pressure, then follow the line back to the air source.  The air source should be either directly from the 12V air compressor or that 3 gallon air tank in the right rear wheel well.  Now determine why air is not getting from the air source to the slide seal regulator.

Finding your air leaks will most likely eliminate your loss of air slide seal problem.  An air source blockage or a kinked air line is possible, but not as likely.

You have only referred to one 12V air compressor so I'm assuming you only have one. The newer coaches now have two 12V air compressors.

Let us know what you find...............................