Power jack getting power.

[OffTheCouch]

I had a strange issue today when trying to hook up to take a quick trip. I unhooked from shore power and tried to operate the power jack. It didn't respond. The systems monitor says my batteries are full. The trailer has been sitting since September. Since that time it's been plugged into shore power, but I don't remember if I had the battery disconnect set to USE or STORE.

Either way, there are two strange things going on:

1. The monitor says the batteries are full, but when unplugged from shore power the jack doesn't work and my interior lights aren't working indicating that the batteries are not charged.

2. After plugging back in, switching the battery disconnect switch to USE the jack started working again.

Any thoughts? Are my batteries dead? Bad battery disconnect switch?

Thanks for any insight, -Andy

[TinShack]

The jack should be wired directly to the battery through a fused wire connection, so would be unaffected by the battery disconnect. The lights however would not work with the disconnect in store mode. I would think the problem would be at the batteries, either bad batteries or a bad connection.

If it's been plugged in since September with the single stage converter that comes with the Airstream, it may have fried the batteries. Did you check the battery water level or are they the maintenance free type or AGM? Does the monitor show the batteries are charged when unplugged?

[alano]

Originally Posted by OffTheCouch

Either way, there are two strange things going on:

1. The monitor says the batteries are full, but when unplugged from shore power the jack doesn't work and my interior lights aren't working indicating that the batteries are not charged.

2. After plugging back in, switching the battery disconnect switch to USE the jack started working again.

Any thoughts? Are my batteries dead? Bad battery disconnect switch?

Thanks for any insight, -Andy

1. When plugged in your monitor says the batteries are full because your converter is generating 12 V. When you unplug, your converter is no longer operating and your batteries take over. Since the jack nor the lights work when in the USE position your batteries are toast.

2. After plugging back in, when you select the USE position, you're connecting your converter again to the batteries and holding 12 V so your jack starts working again.

Replace your batteries and don't leave the trailer connected to shore power while the USE/STORE switch is in the USE position. This will overcharge the batteries and damage them.

[Drathaar]

It might be something really sneaky. The aluminum cover for my propane tanks has a little notch for the Jack wiring to pass through. It lands right over the Jack fuse holder, and if you're not careful, it can cause an open circuit to the jack. Your problem might be different, but check it.

[OTRA15]

Originally Posted by OffTheCouch

[snip]
Any thoughts? Are my batteries dead? Bad battery disconnect switch?

Thanks for any insight, -Andy

Assume you will check water level in batteries cell by cell (using proper caution and safety measures) and inline fuse near power jack switch (plus integrity of wiring nearby). Please leave the trailer unplugged from shore power, put the system in "Use" mode, and report back on the battery voltage readout and so forth.

What type of batteries do you have, and what is their age? Are they the original batteries? Do other 12 volt functions in the trailer work OK, including the furnace, fridge, lights, etc.? [shore power still disconnected]

You could check the voltage at the switch for the jack or inside the fuse holder too, with a voltage meter.

Please report back and good luck!

Peter

PS - Here are some recent threads with similar issues:

http://www.airforums.com/forums/f516...ud-145121.html
http://www.airforums.com/forums/f457...wn-144412.html
http://www.airforums.com/forums/f238...up-144401.html

[Mymosaicmess]

This happened to me recently and it was a result of a blown fuse. I just covered it in foil (not the safest I know, but I was desparate and needed to do a MacGyver) until I was able to replace the fuse.

[alano]

Andy says the jack started working when connected to shore power and the Use/Store switch in the Use position. If the fuse was blown this wouldn't happen.

[delongj]

Just a thought. My jack has a light on it that turns on by a switch on the jack pole. The light works when I am on shore power or connected to the truck power without the A/S batteries installed. (I do use a battery when camping or traveling - just not while in storage). Another area I would check is the grounding of the batteries and the converter connections for gremlins. jd

[alano]

Originally Posted by delongj

Just a thought. My jack has a light on it that turns on by a switch on the jack pole. The light works when I am on shore power or connected to the truck power without the A/S batteries installed. (I do use a battery when camping or traveling - just not while in storage). Another area I would check is the grounding of the batteries and the converter connections for gremlins. jd

Good point, a poor ground connection to the negative battery terminal would also explain the symptoms.

[NY24]

Immediately after unplugging from shore power, a meter will show a false high reading. You need to wait an hour or so before the meter reading will be accurate. As already mentioned, ensure that the electrolyte level is correct.

[Barretta2]

I can't help you, but am hoping someone on this thread might help me figure out what's up with my jack switch. It works perfectly when lowering my rig, but when I toggle it up to raise the tongue, it is hit-or-miss: if I fiddle with it a bit, it will work. I think I may have a faulty switch, but maybe I'm pushing it too hard. (If it is a faulty switch, are they $$ to replace?) Thanks!

[Wingeezer]

On a related subject, sometimes taking a meter reading of voltage can fool you.

The lat time our tongue jack quit working, the first thing I did was to check teh supply voltage at the power head and it was fine.

As well, the light on the jack worked as usual, so my initial thought was that my problem must be with the motor itself, the operating switch or limit switch.


But then, I just noticed that when I hit the motor switch, the light went out. That made me wonder about my ground connection and sure enough, that was all it was - cleaned the ground and back in business.

The corroded ground connection didn't stop me from getting a good voltage reading (voltmeter needs virtually no current to operate) and it would also operate the small light, but it was not capable of passing the higher amperage to operate the jack motor.


Brian.