Forum Discussion

rutzbeck's avatar
rutzbeck
Explorer
Feb 28, 2016

Happijac problem

It was looking like spring today and we are down to dirt so I thought I would put the jacks back on and remove the camper so I could clean the truck up. I got all the the jacks on and connected. When I went to put the jacks down one of the front jacks wouldn't do anything. I rechecked my connections and they were good. There is no power at the jack. I went to the board in the camper and I hear a click but nothing else. Is there a fuse in the board that might of blown. It is a wireless set up. I just had both sets of batteries changed in the camper and the truck due to total dead batteries in the camper. The truck had to be jumped twice before the problem was found and fixed. I don't see why that would effect it but since the problems came back to back I thought I would mention it. Any ideas?
Truck Campers
  • MN_Ben's avatar
    MN_Ben
    Explorer
    Feb 28, 2016
    If there are relays, you could try to swap them to see if that is your issue.
  • MN_Ben's avatar
    MN_Ben
    Explorer
    Feb 28, 2016
    If there are relays, you could try to swap them to see if that is your issue.
  • Oldtymeflyr's avatar
    Oldtymeflyr
    Explorer
    Feb 28, 2016
    If you go to the receiver board and remove the cover you will find fuses. Also, if the jack has not been run for a long time you may want to loosen it up with the hand crank.

    Good luck, let us know.

    Rick
  • HMS_Beagle's avatar
    HMS_Beagle
    Explorer
    Feb 28, 2016
    Yes, there is a fuse for each jack on the controller board. You could also try swapping the jack to a different location to isolate jack problems from controller/wiring problems.
  • rutzbeck's avatar
    rutzbeck
    Explorer
    Mar 01, 2016
    The fuse was blow and I replaced it. The jack still didn't work. I tried changing the jack to another place on the board but it still doesn't work. I think the problem is at the jack. The board makes a noise when I try to get the jack to work. I'm headed to Whitehorse, Yukon so I guess the RV place will have to look into it.
  • MN_Ben's avatar
    MN_Ben
    Explorer
    Mar 01, 2016
    Does it work with the hand crank? Maybe it is stuck, like something fell into the gear when it got moved around.
  • Troutguy's avatar
    Troutguy
    Explorer
    Mar 01, 2016
    OP,

    Did you attempt to hand-crank your problem jack with the manual handle? I accidentally bound up one of my jacks and it unknowingly blew a fuse. I replaced the fuse but it was bound up so tightly that it blew the new fuse.........The solution was using the crank handle to free the gears and then the motor could operate it properly.
    Lesson learned was to be more diligent when approaching the end of the travel range when raising or lowering.
  • joerg68's avatar
    joerg68
    Nomad III
    Mar 01, 2016
    The happijac motors seem to be prone to water intrusion / corrosion damage. Our camper had one motor completely seized after only 2 years. Same symptom: No voltage, new fuse blows right away. At least the control board doesn't get damaged.

    As others have suggested, manually cranking it free might work. But if it is as corroded as mine was, only a new / rebuilt unit will help.

    Dood luck, Joerg
  • rutzbeck's avatar
    rutzbeck
    Explorer
    Mar 01, 2016
    I am going to try the hand crank method today. I have been reluctant to try as I am not sure exactly how it works. I have a lever on top and I expect I pull that down then crank. When I am done will just putting that back up re-engage the motor?
    Thank you for the help
    As to water intrusion it is very possible. I live where it rains about 70 inches a year and we have had more than that. I do take the jacks off in the winter and put them in the garage as that seems to keep them from rusting. The jacks are about 4 years old. I would of thought it would of been the rear passenger side jack that went bad as it groans the most when I use it.

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