Installing electric tongue jack

Hi,

I have a question about what might (did) go wrong if I make a mistake wiring my new Ultra 3502/3500 Electric Tongue Jack.

It bolted in quick, no problem. I disconnected from shore power. I took out the fuse that was already connected to one of my 6v batteries, connected the line DIRECTLY to the battery (probably my big mistake), turned on the jack and... now I have no battery power. I reconnected to shore power and the lights, fridge, fan - all of it works. But when I unplug from shore to run the two 6V I get nada. I know that the batteries were fully functional because I tested them before starting.

Did I fry something expensive? Can this be fixed?

Thanks,

Jason
2007 2720
TV 2006 Quest Minivan

[MudDog]

I have a Barker tongue jack on order...from previewing the install directions, I don't know that you did anything wrong. The jacks use the frame for ground and typically connect to the postive terminal. The power lead usually has an inline fuse for the jack from what I gather.

I have two 6 volt batteries and there is a 30 amp fuse going to the TM, but there is also a 75AMP fuse between the two batteries. Did you check/test both fuses?

If both fuses check out OK, then if the fuse you removed was the 30amp that feeds the TM, I would also check the fuse holder, especially if it is the original glass fuse holder. They are known to cause problems and perhaps when you took it out and put it back in you are no longer getting a good connection.

From reading this forum, I replaced the glass fuse holder with a Mini-ATC fuse and holder.

Thanks MudDog. So in theory, I may not have done any damage.

What you say makes sense, since there was a burn on the inside of the fuse holder, but the fuse itself wasn't fried through. This particular electric jack is internally grounded - according to the instructions, and I don't see any other grounding wire.

If I don't connect directly to the positive side on the battery, where else would I connect? And if you do connect to positive, then whey didn't the jack work? I'm going to change the fuse holder and hope that the batteries are still good.

Jason

[MudDog]

Internally grounded just means there is no wire for the ground....bolting it to the frame is grounding it.

For power the jack connects to the positive terminal on the battery - so to me it doesn't sound like you did anything wrong.

When you get the new fuse-holder (Walmart sells one, but it does not have a cap to protect from the weather....auto parts stores carry one just like it, but it has a cap cover). It should be a mini-ATC fuse holder rated for at least 30 AMPS. Something like this:

http://www.radioshack.com/product/in...entPage=family

You may also want to get a volt meter or multi-meter to test voltage/continuity, etc.

I was having trouble with my exterior patio lights and ended up getting a digital multi-meter this weekend at Lowes to troubleshoot (turned out my switches were acting up....probably from the previous wash).

I bought a good digital meter at Lowes. I'd stay away from the $10 Wal-Mart meters. The meter is an essential tool in toubleshooting any electrical problems.

The meter can also be used to test fuses, or often times the variety fuse pack's sold at most hardware/auto stores include a fuse tester.

The jack may not have worked for a few reasons:

1) if you have a 75Amp fuse like I do between 6 volt batteries and that blew, you would only be getting power from one battery (6 volts), not enough to power the jack)

2) The jack itself blew a fuse - did it have an in-line fuse or a fuse under the housing?

3) You don't have a good ground connection for the jack. As mentioned they are grounded when you bolt it to the frame. I've heard of people having to scrape away paint to make sure there is good metal on metal contact....also if you have a swing hitch, you may have to run a jumper wire from one of the 3 jack bolts to the other side of the a-frame to get a better, more constant ground connection (even though my jack is in the mail, I've already run a jumper wire because I have a swing hitch and have read about ground issues).

If the 75A fuse is in series between the two 6V batteries and it blew. you will get no voltage to any of the appliances. I suggest you add a heavy gauge wire from under one of the jack mounting bolts to one of the bolts main frame. The one used for the safety chain is a good choice. This way you always have a good ground. If you put the wire on the hinged side of the hitch, you can still operate the swing hitch with little slack. The swing hitch moves slightly in transit and hence the areas of contact of the front frame to mainframe will have the paint scraped off, but will rust in time and cause a poor connection.

It does seem likely that I need a ground wire from the jack to get past the swing hitch. I called the manufacturer and they told me that they had reported problems of the jack not working because of improper grounding.

Jason

You called it mudDog.

The problem with the batteries was the that the fuse holder was fried, and when I replaced it with the modern square shaped fuse holder the batteries were fine; and two, I ran a ground from the jack to the same ground spot that the 6Vs are grounded to, and now the electric jack works perfectly.

I appreciate the feedback.

Jason