Most likely causes (in order of likelihood)

  1. Low hydraulic fluid in the pump reservoir — fluid can't fully retract jacks. The #1 cause.
  2. Low DC battery voltage — controller faults out and stops the cycle.
  3. Controller error code that needs to be cleared (often a timeout from a slow cycle).
  4. Stuck or failed solenoid valve.
  5. Failed pump motor.
  6. Jack frozen to the ground (winter camping) or sunk into soft surface.
  7. Failed control switch.

Diagnostic steps (in order, free/cheap before expensive)

  1. Check the hydraulic fluid first. The reservoir is usually in a basement compartment and has a sight glass or dipstick. Top off with Dexron III ATF (unless your manual specifies a different fluid). Important: check with all jacks fully retracted for an accurate reading — fluid in extended jacks is not in the reservoir.
  2. Check battery voltage with a multimeter. You want 12.5V+ at rest. Below 12V, plug into shore power or run the generator before attempting retraction.
  3. Check fuses on the controller — there's usually a main fuse and individual jack fuses.
  4. Try the manual override procedure for your specific system. Lippert: there are typically manual release valves on each jack cylinder, plus an emergency retract button on the controller. Refer to your manual.
  5. If the pump runs but jacks don't move, suspect the solenoid valves. If the pump doesn't run at all, suspect controller or wiring.
  6. If a jack is frozen to the ground or sunk in mud, warm it with a hair dryer (frozen) or place a board under it before retraction (sunk).
  7. On any error code, write the code down and look up the specific meaning in your controller manual — Lippert codes especially are well-documented.

DIY vs. call a tech

Fluid check and top-off, battery check, fuse check, and manual override are DIY. Solenoid replacement is intermediate. Controller and pump replacement are typically tech-level.