I had a similar problem last week when cold weather caught us. The jacks retracted very slowly, and then failed to operate at all. In addition to what has been mentioned by others here, I found two blown fuses in the metal box under the steps near the batteries. There are about 10 automotive blade style fuses inside this box, and none of them are labeled as to their function.
After topping up the hydraulic fluid (Dexron/Mercon automatic transmission fluid), resetting the black circuit breaker on the chassis frame near the pump, and replacing a blown 5 amp and 15 amp fuse in the box near the batteries, all was well again.
Two questions for the group:
1. Does anyone have a list showing the circuits protected by the fuses in the box near the batteries?
2. Does anyone know the location of the Lippert leveling control module? Lippert says it should be attached to a basement compartment ceiling, but I have not found it. There is a blocked pass through area for slide out power cables and LP hose, that's about the only place left that I can think of. Thanks.