Newbie Tongue Hitch Question

[dwisser1]

FCI 3500 power tongue jack. Got home from a long trip last weekend and backed up the trailer into the driveway, but when I went to take off the WDH, the tongue jack would not work. So I manually did it, which I don't want to do again. So, I checked the fuse, it's fine, but replaced it anyway with 30Amp 24 Volt fuse. Power to the switch, but no power out. So I replaced the up/down switch. I knew that was going to fix the problem, but it didn't. I cleaned the grounds by removing all 3 bolts, but nothing.
So, I have an appointment at the service dept for some warranty work and I thought maybe they could test the motor while I had it there and if it needs a whole new unit, I'd buy one and install it myself.
Tonight, i was hooking up the trailer to truck (manually) and after I hooked up truck power to trailer, the tongue jack worked. (?). What I am confused about are the following:
1. I tested my batteries, they are fine.
2. I tested the components in my trailer that run off of 12V, like the lights, they worked
3. The tongue jack didn't work even when the power was plugged into a 30A plug in.
4. It only works when it is powered by the truck.

Thoughts?

[jpgale]

I can not help to diganose the issue for you, but I had the same jack it also died on me in very similar ways. I replaced it with a far better jack. The FCI on the 2018's is junk just get a good one.

I got https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

James

Originally Posted by dwisser1

FCI 3500 power tongue jack. Got home from a long trip last weekend and backed up the trailer into the driveway, but when I went to take off the WDH, the tongue jack would not work. So I manually did it, which I don't want to do again. So, I checked the fuse, it's fine, but replaced it anyway with 30Amp 24 Volt fuse. Power to the switch, but no power out. So I replaced the up/down switch. I knew that was going to fix the problem, but it didn't. I cleaned the grounds by removing all 3 bolts, but nothing.
So, I have an appointment at the service dept for some warranty work and I thought maybe they could test the motor while I had it there and if it needs a whole new unit, I'd buy one and install it myself.
Tonight, i was hooking up the trailer to truck (manually) and after I hooked up truck power to trailer, the tongue jack worked. (?). What I am confused about are the following:
1. I tested my batteries, they are fine.
2. I tested the components in my trailer that run off of 12V, like the lights, they worked
3. The tongue jack didn't work even when the power was plugged into a 30A plug in.
4. It only works when it is powered by the truck.

Thoughts?

[RogerR]

Check your bolts to the frame. You may not have a good ground. I added a ground wire from the mounting bolt direct to the battery as it happened to me on a prior trailer. You can also clean and shine the point where the bolt goes into the jack, add a star washer, etc. to improve grounding.
Or it was just bad out of the box.

[mokurt]

Originally Posted by dwisser1

4. It only works when it is powered by the truck.

Thoughts?

When I added a power jack to my trailer it is wired directly to one of the batteries on the tongue.

I don't know were your batteries are located but I would trace/check the powered jack wire without tow vehicle connected.

[dwisser1]

Lazy Days found a fuse in the junction box on the frame that was blown. I had no idea there was a fuse in there.

[Camper_bob]

Originally Posted by dwisser1

Lazy Days found a fuse in the junction box on the frame that was blown. I had no idea there was a fuse in there.

You may want to replace that fuse with an auto-reset breaker. If you run the jack to its limits (up or down), even for just a second, it is likely to pop that fuse.

My OEM FIC 3500 jack died from drowning (water intrusion); replaced it with a Husky that had better water protection, and an auto-reset breaker as well as ball bearing drive. WAY better jack in EVERY way!

[RogerR]

Keep a spare for every fuse in the camper in a kit. Also have a spare tongue breaker in your kit as they are outdoors and can go bad or corrode.
I have always kept a bucket over my jack when parked for storage. Cheap insurance. I put the end of my 7 way up in the bucket to keep it out of the weather. I use the chains to hod the bucket down and keep it from blowing away.

[Jagiven]

Originally Posted by RogerR

Keep a spare for every fuse in the camper in a kit. Also have a spare tongue breaker in your kit as they are outdoors and can go bad or corrode.

I keep lots of spare fuses. When you blow one, you usually blow a bunch diagnosing what is wrong. An auto resetting circuit breaker fuse for the tongue jack should be mandatory.

I keep a pile of spare fuses in a large tic tac container. Works nice, I can see what I have at a glance.