Air pressure problems where is VDC

[Brassmonkey]

I have a 2002 Itasci Horizon 39.9 with 2 slides freightliner say the VDC is under bed it's not,, and have looked in engine area with no luck I know it's got one, does anyone know where they hide it? rear air gage is flying back and forth and the air is ok, it stops after it gets warm. Thanks

[RV Wizard]

Have you recently bled air tanks? Does your coach have an air filter/drier? Have you had it changed out in the last two years? You should. You could have water contamination that might cause this kind of problem but it could also be other issues like gage or sensors.

[J Walker]

The VDC is placed by the MH manufacturer not Freightliner. I had a pressure on one tank go from low and then quickly back to normal. I had no doubt that it was just the readout that was at fault since the pressure would not behave that way. Indeed I did confirm that there was pressure in my tanks. The fix was to replace the VDC which is relatively common problem. It always seems to be the pressure that fails. You have two air lines connected to the VDC which converts it to a digital pressure reading. There must be something in the conversion to digital that fails. I say contact Itasca.