Diagnosing Slow or NON-Retracking Jacks

WARNING: LOOSENING A HOSE OR CHECK VALVE CAP WHEN A JACK IS EXTENDED
COULD ALLOW THE VEHICLE TO DROP SUDDENLY CAUSING SEVERE INJURY OR DEATH.
DO NOT CRAWL UNDER THE VEHICLE UNLESS THE FRAME OF THE VEHICLE IS PROPERLY SUPPORTED.

If a jack will not retract or is slow to retract, and you are confident your springs are good, the problem is the jack, the solenoid valve, the velocity valve (if so equipped) or the hose.

  1. Manually open the solenoid valve. Does the jack retract? If so, your issue is either the solenoid valve itself or the electric/controls.
  2. If the jack does not retract, close the solenoid valve. Go back to the jack in question & slowly crack/loosen the hydraulic hose from the jack to release pressure/fluid (go slowly & have a rag ready). If the jack does not retract properly, continue loosening the hose & if fully removed still does not retrack, you need to replace the cylinder (not the entire jack assembly!). This is a job that most RV Dealers/Service Centers/Mobile RV Repair can typically perform in their shop or onsite at your campground/parking area (albeit not fun without a lift!). We stock most common models & can save you $$$ vs. buying through them or HWH and can also help you through the replacement process.
  3. If the jack does start to retract once the fitting is cracked, quickly tighten the hose. We now know the cylinder is mechanically working, so the issue is upstream between the solenoid valve & the jack cylinder.
  4. Crack/loosen the hose (for that jack in question) at the manifold. If the jack does not retract, there is a problem with the hose, such as a kink. Inspect the hose from the manifold to the jack cylinder. Could be as simple as a kink/restriction.
  5. If the jack retracts after cracking the hose at the manifold, and is equipped with a velocity valve, the velocity valve is most likely the problem.
  6. If there is no velocity valve, there may be a problem with the solenoid valve or possibly the outer check valve.
  7. Before diagnosing a potential solenoid valve issue, check for blown fuses. (310/610 on the aluminum control box, 325/625 on the plexiglass faced control box, and 725 in the wiring at the motor/pump/tank).
  8. To diagnose a solenoid valve issue, swap the 2-wire connector from a known good solenoid valve (one of the other 3 that you know works) & press STORE on your touchpad. If the problem moves from the cylinder that wasn't retracting over to the one you swapped with, then you will need to do some electrical diagnosis (more info to come, but best place to start is the service manual for your system). 
  9. If the problem stays with the original jack, replace the solenoid valve. There are two standard solenoid valves on HWH systems; LARGE & SMALL

DON'T FORGET TO SWAP SOLENOID CONNECTORS BACK TO CORRECT POSITION!

PLEASE NOTE: The system will automatically shut off after pressing STORE on the touchpad approximately 2 minutes after the last red jack down warning light goes out. If one or more red jack down warning lights do not turn off, the store mode has a timer to shut the leveling system off 20 minutes after the "STORE" button is pushed. Allow the system to stay off at least 30 minutes before pushing the store button again. Recycling the STORE mode immediately after the touch panel turns off may overheat the solenoid valves. If it is necessary to eliminate the 30 minute waiting period, open the manual valve release to allow the jack to retract fully. The system should be serviced as soon as possible.