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Leveling systems overview

Every auto-level system does one job: a tilt sensor reads the coach, and the controller runs jacks until that reading matches the zero point it saved. Electric or hydraulic, 4-point or 6-point, the rest is how it moves the jacks and what stops it.

The short version

Electric or hydraulic: what's on the frame

Lippert Ground Control (sold as Ground Control 3.0 until Lippert dropped the number) is electric. Each landing gear leg and jack has its own Hall effect motor, and the controller runs them singly or in pairs. Lippert doesn't sell a hydraulic Ground Control: if a fifth wheel has a pump and hoses, it's Level Up.

A hydraulic system has one 12 V motor and pump, a reservoir, a manifold of solenoid valves, hoses and a cylinder at each corner. Lippert hydraulic systems use a pressure switch so the controller knows the jacks are holding retracted. Older Power Gear motorhome systems use spring-return jacks with a dump valve, and a float or pressure switch runs the jacks down light.

Power Gear also built an electric jack system for motorhomes. Its touch pad, 140-1226, is the same part number used on some Power Gear hydraulic kits, so look under the coach before you open a manual.

SystemTypeWhere you'll see itJacks
Ground Control (3.0)Electric, Hall effect motorsFifth wheel4-point: 2 landing gear, 2 rear. 6-point adds 2 middle stabilizers
Ground Control TTElectric, Hall effect motorsTravel trailerRear and front jacks plus a power tongue jack
Level UpHydraulicFifth wheel (also a 4-point TT version)Hydraulic landing gear plus rear jacks, 4 or 6 point
Level Up motorhome, LCI Class CHydraulicMotorhome4 jacks working in like-side pairs
Power GearHydraulic or electricMotorhome, older units4 jacks
HWH 625 seriesHydraulicMotorhome4 jacks, extended in pairs
Equalizer (EQ Smart-Level)HydraulicMotorhome and trailer4 jacks

What the controller senses

The level sensor is a tilt sensor that reads front-to-back and side-to-side angle. On Lippert fifth wheels it's inside the controller, with a second remote sensor at the rear: 'External sensor' is that rear sensor or its wire, and 'Internal sensor' means the controller itself. The controller knows nothing about the ground except what jack current or hydraulic pressure tells it.

That's why mounting matters. Lippert says the controller and rear sensor must be oriented the way their labels show and fully secured, and it lists an unsecured controller as a cause of 'Excess angle'. Power Gear mounts its control box upside down in the center of the coach with the arrow pointing forward. If the box moves, every level after that is off by the amount it moved.

Targets differ. Equalizer's auto level aims for 0.5 degree front-to-rear and side-to-side. Lippert motorhome systems won't auto level when the coach is 3.5 degrees or more out either way.

How auto level runs, step by step

The order is built so the frame never twists. Watch one full cycle and you'll usually see which corner is late, slow or quits. This is Ground Control 3.0 on a fifth wheel:

  1. Start with the front above level (hitch recognition needs it). The front lowers slightly below level.
  2. The rear jacks come down and touch ground.
  3. Side-to-side leveling runs. On a 6-point, the middle jacks ground to stabilize but don't level.
  4. Each jack makes a final ground touch, and the pad reads 'Auto level success', then 'Ready, jacks down'.

Other systems run a different order

Level Up on a fifth wheel drops the landing gear until the front is below level, lifts it back to level front-to-back, extends the roadside jack, then the curbside jack, and runs the landing gear again to finish. It may make more passes after that.

Lippert's motorhome Level Up grounds the jacks one at a time starting at the low end, lifts that end to level, grounds the rest the same way, then levels fore-aft and side-to-side, repeating until it's there. On every system, people moving inside the coach can spoil the cycle: Lippert lists it as the cause of 'Unable to finish leveling'.

The zero point is the sensor reading the controller saved as level, and every auto level drives back to it. Saved a degree off, the coach levels a degree off every time. The next lesson covers setting it.

Power: what each system wants

Controllers shut down on sag under load, not on a flat battery, so a battery that reads fine at rest can still stop a cycle. Load test before you chase any leveling complaint.

SystemNeedsStops atSupply
Ground Control 3.012.75 V minimum, 12 V or more under loadBelow 10.8 V50 A breaker recommended (OEM supplied)
Ground Control TT12 V or more under loadNot listed30 A fuse on the battery feed, 50 A circuit per RVIA
Level Up fifth wheel12 V, full charge or shore powerBelow 9.5 V50 to 100 A protection per RVIA and OEM (80 A breaker listed)
Lippert motorhome hydraulic12.7 V to start auto (12.75 V on Class C); manual runs above 9.5 VBelow 9.5 VRun the engine
HWH 62512.7 V at rest, at least 9.0 V at the pump motor runningNot listedDraws up to 200 A
EqualizerBattery that holds 150 A at 10.5 V for 30 secondsAbout 10.5 VUp to 160 A at the pump, 4 gauge cable minimum

On the job

  1. Identify the system: hoses and a pump means hydraulic, a motor on each leg means electric. Read the controller label for the model.
  2. Load test the battery and read voltage at the controller or pump while the system runs.
  3. Check that the controller is tight and oriented per its label.
  4. Run one full auto cycle and watch which corner is late, slow or quits.
  5. Write down the exact message or light pattern before anything clears it.
  6. When it finishes, check the coach with a carpenter's level on the floor at the center.

Numbers

Shop tip

Watch one full auto cycle before you touch anything. The jack that's late, slow or quits early is where you start, and you'll see it faster than any code will tell you.

Where this comes from