Troubleshooting Electric Trailer Jack JET-5000

Question:

The lights work but jack wont, we heard a click but doesnt go up or down! He checked the ground what else should we do?

asked by: Larry U

Helpful Expert Reply:

If a trailer's interior lights, or the built-in LEDs on the jack, work when powered by a trailer-mounted battery but the electric tongue jack itself does not, the two most common causes are a weak ground and a battery that needs charging.

It is quite common to have a ground issues develop over time since water and dirt can become trapped inside the gap between the trailer surface and the jack's round mounting flange. This foreign material, and even the paint on the trailer frame where the jack mounts, can cause a grounding issue. The best remedy is the remove the jack, and sand off any paint, primer or rust on both the bottom of the jack mount and the top surface on the trailer. Ideally you will have bare metal on bare metal.

Before you re-install the jack to the sanded surface on the trailer apply dielectric grease # 11755 to block any other contaminants from getting in there and causing future issues.

Keep in mind that the battery on your trailer will receive only a light trickle charge from the connection to your tow vehicle's 7-way. That charging circuit is intended to maintain a charged battery but it cannot re-charge one that is depleted. That takes a charger like # CTEK56353.

Some trailer lights, especially the super-efficient LED type that appear more and more in RVs, require so little power that even a nearly dead battery can still light them. So just because lights still work that does not mean the battery necessarily has a good charge on it.

Naturally you should also check that the +12V power wire has a solid connection to the battery or junction box it is connected to.