03 Revolution slide power problem.

[dperetti]

Just found out the large living room slide will only operate when plugged into shore power. (Bedroom slide which is considerably smaller, operates fine on either power source.) Am getting good battery voltage at the slide controller (without shore power), but it will only budge slightly with the engine running. (Fleetwood recommends engine running for slide operation.) Also have noticed Xantrex is going into Inverter mode on its own when underway. Don't know if this is related but am beginning to think there is an inverter or transfer switch problem. Batteries one year old, good hydrometer test, and checked all connections as well as grounds. Any ideas out there?