I hope this has an easy answer. My aux. air tank guage goes to 0 almost immediately after turning bus off. However no leans. If the ignition key is turned on immediately see the normal pressure. The aux. air compressor only goes on everyother day or so. If I leave the aux. compressor off then the pressor will read lower than normal with ignition on. that pressure drops as use the toilet, or air pocket doors etc which is normal.
I hope this is normal (guage only working with ignition on) since everything else seems okay.
Thank you for any information.
Kim Sloan
02 Vantare XLII S2
06 Dodge Megacab