Hi jbeallen,
Welcome to the Heartland Owners Forum. There's a lot of great information here along with a great group of friendly people.
The hydraulic pump operates slides and landing jacks (depending on how old the unit is, and whether it has 4 or 6 point leveling, some things will vary). There's a row of automotive type 12V circuit breakers near the battery, one of which provides power to the pump.
To operate the hydraulics manually, you use a drill with hex bit to turn the pump motor one direction or the other to push or pull fluid. You also have to manually open and close the valve controlling the slide or jack(s) using an Allen wrench.
If you look in the
TOOLS/HOM OWNERS MANUALS section of the forum, you'll find the written procedure along with photos.
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