What would cause/allow all 6 tires to deflate when CTis is supposed to be inflating?

[insas]

Thanks for the replies / advise. I have checked the tires, they are in very good condition (practically new). -This has only happened twice and I have aired them up by hand the next day at the latest. The lowest pressure driven on was 35 psi.

Ok, so I aired up all 6 tires to 80 PSI so I could check for leaks, etc... The middle drivers side tire has(d) air flowing through the wheel valve afterward, not sure where it's going as I couldn't find an external leak anyware... but you could hear and feel it until the tire PSI dropped to 72, then it stopped. Does this mean I have a bad wheel valve or something else? No other leaks that I could tell. The controller is disconnected right now for troubleshooting.

Thanks again!

 

[Suprman]

You can take apart the wheel valve and clean it. There is a rubber flap/seal and a spring. Water in the air system causes corrosion of the valve body and the flap wont seal tight since the internal surface is no longer smooth. The air leaks back into the ctis system you dont really notice it coming out it probably seeps out the quick release valves. A leaky wheel valve will cause flat tires over time but it should not cause a controller error since the system can still fill air into the tire. You can take the output line from the valve body on the cab floor and hook it to a compressor and look for leaks. Dont let it run for too long if the tires are taking air you could over-inflate them.