Terry, the auxilliary pump works only when you use the Auto Level feature, at least on mine. The system automatically levels the coach in camp and maintains it by checking for level every so often, as Gerald talked about. On my rig at least it seems the maintenance part of it comes only from the auxilliary pump and not the tanks. If the little pump is operational it should indefinitely maintain things. But the pumps are frought with various possible maladies such as poor electrical connections and dirt from being in a relatively unprotected chassis location. If it's working, you should hear the little pump, under the passenger front corner, fire off occasionally as it's informed by the HWH controller during the periodic level check that things have gotten out of whack since the last check.
If you've been leveling in camp by using individual buttons on the display instead of Auto Level, then you've thereby taken the auxilliary pump out of the picture, so it can't help offset any leakdown over time. If you have been Auto Leveling and never hear the pump come on and run for awhile, then you likely have a failed pump or faulty connections. If you hear the pump once in awhile but still go off-level over time, or the pump never stops running, you likely have a serious leak somewhere or the hose from the little pump is compromised.
Many here have replaced their factory auxilliary pump with a Viair brand model 380, as per Gerald's suggestions in many previous threads. The only precaution is providing better electrical wiring to the new pump so it can operate properly and safely.
Joel
