Lost 12V when unplugged from shore power

**sourdough** · 03-14-2017, 01:07 PM

Sometime during our stay in FL I must have lost my 12V to the trailer.

When on shore power everything works fine. When unplugged from shore power most 12v items stope; no lights, the fridge won't kick on BUT the slides work great. I assumed I must have a blown inline fuse. I have two on the frame both are good. I get good voltage from the batteries into them and out. I have no blown fuses in the power panel. I checked the fuses in the fridge as John suggested but they are OK. When I put a meter on the 12vdc input to the fridge while plugged into power I have 12vdc (and it works fine). When the 120vac is unplugged I don't have 12vdc and it won't switch to LP. I am assuming there is another fuse somewhere inline on a 12vdc lead that splits off after it powers the slides. OR maybe a bad 12vdc disconnect? I tried turning the disconnect on and off and nothing changes. I can't crawl under the trailer due to physical limitations but I can't imagine a fuse placed in the underbelly for part of the 12vdc equipment.

Thinking about it, reckon the slides would operate if the disconnect was bad? I'm going to post this and run out to see if I can pull the disconnect and see if it tells me anything. Thanks for any ideas.

**JRTJH** · 03-14-2017, 01:24 PM

Two possibilities: A loose connection on the 12 VDC disconnect or a bad disconnect switch. Second, possibly a bad 12 VDC circuit breaker? There are two on the tongue, one goes to the disconnect switch and then to your 12 VDC distribution panel (lights, reefer, water pump, etc) the other goes to your slides, tongue jack, stabilizer jacks, etc.

From what you've said, all of the 12 VDC wiring and circuitry inside is good (it all works from the converter) and all the wiring from the battery is good (at least the battery, wiring to the slides, etc) so that only leaves the wiring from the battery to the disconnect switch, through it and to the converter 12 VDC distribution panel. So........ gotta be the wire to the circuit breaker, the wire to the disconnect switch, the disconnect switch itself or the wire from the disconnect switch to the converter fuse panel.

**sourdough** · 03-14-2017, 01:35 PM

Wooo Hooo! Bad disconnect.....or a disconnect that wants to go bad.

When I discovered I had this problem when we disconnected to leave FL I checked the disconnect at the first stop, but, all I did was turn it on and off to see if it was accidentally off (although it was pointed to on). I had intended to pull it and check it with a meter but forgot until I wrote the above email.

When I pulled it and put a meter on it (I had put it to off) I read no continuity from one post to the other.....good. I turned it on and read garbage. Turned it off and it read right. Turned it on again and NO continuity...hmmmm. Flipped it back and forth quite a few times and read it again. No continuity when off and continuity when on. Heh heh! Had DW go inside and the lights and fridge work when it turned to on now and go off when it is turned off. So, it is apparently fixed but I think the disconnect is suspect. I'll get one and replace it. Sorry I posted so quick before I had finished my trouble shooting but this little episode might help someone in the future. Thanks again John for the help.

PARAPTOR · 03-14-2017, 01:45 PM

been chasing this post around, I posted on the other thread, Glad to hear it was the disconnect switch and nothing else

**sourdough** · 03-14-2017, 01:50 PM

Thanks PARAPTOR.

**JRTJH** · 03-14-2017, 01:52 PM

sourdough,

You can get a replacement switch at Tractor Supply for about $10 or from the dealer for about $35... Probably made at the same factory in China...... Glad you found the problem... It's always nice to see things "figgered out"....

**sourdough** · 03-14-2017, 02:13 PM

Thanks John. It HAD to be the disconnect unless there were some kind of hidden fuse in the underbelly, which I was sure there wasn't. Now, if we just had a Tractor Supply. Going to our large town an hour away tomorrow so I'll look there....they've got STUFF whereas here, if Dollar Store doesn't have it, you don't get it

**JRTJH** · 03-14-2017, 02:39 PM

LOL I well remember living in a town like that. Right after med school, I did an internship in Bude, MS. The highlight of the day was waiting for the bread truck to make a delivery to the Dollar General..... My DW was not impressed !!!!!

PARAPTOR · 03-14-2017, 02:43 PM

Is the disconnect switch the key type? The labeling on my disconnect switch seems to be backward from how I think

Mine is the key type so regardless of that stupid labeling, if that key is in my hand then there no circuit between the battery and the power distribution panel. For us old Far... simple is essential. Better yet the key is also chained to the rig

So yes I now know where it always is

**sourdough** · 03-14-2017, 03:03 PM

Yes, mine is the key type with the little chain that holds it. Mine is labeled "on" and "off". On means I should have power. Off means the power is turned off. The key comes out but I'm not sure if it does in any position or just when off.

John, speaking of "highlight" of the day; I lived in a town of 1200 folks when I was in high school. One blinking light. Obviously nothing went on.....ever, except football and I was involved in all of it. But, if there was no ball there was NOTHING, except........watching the Ben E. Keith supply truck come into the grocery store about 6am. THAT was primo! All kinds of fruits and vegetables, eggs (which I had to candle), potatoes in 100lb. bags that I got to sort into 10 lb bags. All kinds of stuff I didn't get at home and it was pretty cool.

PARAPTOR · 03-14-2017, 04:13 PM

Ya that is the labeling ON (TRUE) Off (FALSE)

Disconnect switch in ON position ie Disconnect (not connected, no connection) is true ---- POWER OFF (No Connection)

Disconnect switch in OFF position ie Disconnect (not connected, no connection) is False POWER ON (Not not disconnected is connected)

See what happens when one retires and has time to think

See how simple this is

Easier way to look at it, Key in your pocket POWER OFF

CaptnJohn · 03-14-2017, 04:37 PM

Quote:

Originally Posted by JRTJH

LOL I well remember living in a town like that. Right after med school, I did an internship in Bude, MS. The highlight of the day was waiting for the bread truck to make a delivery to the Dollar General..... My DW was not impressed !!!!!

I grew up in a town like that. The big deal was watching the 1 caution light blink and we lived nearly a mile away from that! When I came back from Nam I had orders for Knob Noster MO. Said I rather go back to Nam,,, 2 TDY assignments and I was back.

ctbruce · 03-20-2017, 06:45 AM

Quote:

Originally Posted by CaptnJohn

I grew up in a town like that. The big deal was watching the 1 caution light blink and we lived nearly a mile away from that! When I came back from Nam I had orders for Knob Noster MO. Said I rather go back to Nam,,, 2 TDY assignments and I was back.

Knob Noster is not the end of the world. But it is next door. I think the end is at Warrensburg.....

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