Happy Jac motor problem

The motherboard on a Northstar Laredo is mounted on the outside wall under the sink behind the plumbing. Good luck!!!

You might pull the cover off the main unit inside the TC. My motherboard has two 40A fuses. Check to see if one is blown, if releasing the lever and cranking it manually doesn't show binding as the problem.

that is a good idea use the hand crank and move the jack down a few inches then try the remote.

Super_Dave wrote:

Gary3 wrote:
Release the motor and try cranking it manually,I had one that the bushing in the hole was rusted tight.

Since the camper is on the truck, he should be able to release the motor and stand on the foot of the jack and it will go to the ground.

Only if they are model 4600 jacks.

http://www.happijac.com/index.php/products/jacks/86-products/86-happijac-camper-jack-model-comparison

Gary3 wrote:
Release the motor and try cranking it manually,I had one that the bushing in the hole was rusted tight.

Since the camper is on the truck, he should be able to release the motor and stand on the foot of the jack and it will go to the ground.

Release the motor and try cranking it manually,I had one that the bushing in the hole was rusted tight.

Americamper wrote:
I go to unload and only the fronts will work

I would also be at a loss as what to do .
In not saying that you would do this, just making a general point for others as a reminder .
Those jacks are a weak point in tc design.
So many times I hear of people off loading in remote places.


I guess it's a good thing that your not trying to reload back onto the truck at a campground with someone with a reservation waiting to occupy your site or in the middle of nowhere with no internet service. :h

I have had one motor seize internally due to water damage in about 2 years... so that is certainly a possibility. Just two failing at the same time sounds less likely. Them jacks like to be exercised once in a while...

If a low battery were the reason, and the front motors run, then any single jack should work individually - just not all together.

The clicks you hear are relays in the control box that switch the individual motors on or off. There are fuses in the control box and it is possible that the rear ones are burnt. Replace with same amperage and try again. If the fuses are OK, chances are there is no current going to the rears at all. Possibly a loose connection at either end - do not forget to check the grounds.

It is somewhat possible that the rear jacks are "jammed" in the up position and the motor power is not enough to break them loose. You can disengage the motor head (move the small lever at the side of the jack head to the other end) and try to crank them manually. Once they are extended just a little bit, the motors should work again. If the fuses still blow, either the motor is seized or the gears in the head are jammed.

On the plus side, Happijac are rather quick and customer-friendly when you need spares...

Make sure the house battery is charged and has a good connection.

Its probably the motherboard or remote problem.