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Lost all 12 volt power.

As of a few minutes ago. We lost every 12 volt system on the coach. The house batteries are at 12.8 volts. All the 12 volt fuses are fine. The freedom 25 inverter/charger is charging. No smell at all of burnt wire. When I turned the engine key to on. The dash lit up as normal and air alarms and the relay clicking from front to back were as normal. But no HWH power. I didn't try to turn over the starter (yet)

We have 50Amp 240V into the coach. And all the 120V systems are operating. One thing I do notice is that even though we have ac from the city. The light for the electric element for the Aqua Hot will not illuminate.  I would suspect that with no 12V to the Aqua Hot and it's brain box that the element will be non-operational.

Any advice is greatly appreciated.


Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Lost all 12 volt power.

Reply #1
"Salesman Switch" near entrance door ON?
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Lost all 12 volt power.

Reply #2
And, If the "slesman's switch" is on try doing what I do under mystifying circumstances like yours.
I do the "thump and/or wiggle" test. I go around and thump everything electrical. If that doesn't turn things back on then I wiggle every electrical wire at or near the termination or connection point.
If all those steps fail, I call an electrician.
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Lost all 12 volt power.

Reply #3
I would try disconnecting from 50amp service to isolate power from only the house batteries.

Where did you se that you have 12.8v? On the inverter remote panel?

I have a battery monitor that connects right at the battery so it would still report battery voltage even if the class-T fuse was blown between the battery and the inverter and other 12v connections. On our coach this class-T fuse is on the wall in one of the storage bays.
Bruce & Linda
2004 U295, Build # 6268, ISL400 CAPS
2016 Ford Explorer Sport or 1985 Jeep CJ7

Re: Lost all 12 volt power.

Reply #4
DANG!!! That was it. Thanks for that reminder Brett. Geez! Do I feel like a dolt.

I only mess with that switch when I put the coach in storage. I must have accidentally hit it with my foot when I bent down in the step well looking under the co-pilots seat for the cats ball.  SO, It's the cats fault. :-) :-)



Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Lost all 12 volt power.

Reply #5
Did you check the salesman switch?

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Lost all 12 volt power.

Reply #6
Yep, Right after Brett reminded me. And it were off.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Lost all 12 volt power.

Reply #7
DANG!!! That was it. Thanks for that reminder Brett. Geez! Do I feel like a dolt.

I only mess with that switch when I put the coach in storage. I must have accidentally hit it with my foot when I bent down in the step well looking under the co-pilots seat for the cats ball.  SO, It's the cats fault. :-) :-)

You aren't the first to bump it (or have a pet do so) and not realize it  :whistle: 
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Lost all 12 volt power.

Reply #8
DANG!!! That was it. Thanks for that reminder Brett. Geez! Do I feel like a dolt.

I only mess with that switch when I put the coach in storage. I must have accidentally hit it with my foot when I bent down in the step well looking under the co-pilots seat for the cats ball.  SO, It's the cats fault. :-) :-)

Those cats are sneaky mischievous pets!


Joe & Dottie Allen
Sold!  December 2023.      2000 U320; build # 5645
Our coach " Maxine"
Motorcade #  15922;  Escapee 150950; FMCA F330833; Boondockers Welcome;  Harvest Hosts;  Thousand Trails
'98 U320 from 2000-'06
USAF '62-'66

"Do not spoil what you have by desiring what you have not; remember that what you now have was once among the things you only hoped for." ―Epicurus

Re: Lost all 12 volt power.

Reply #9
We have a small movable metal bracket that prevents salesman switch from rotating from on position.

Re: Lost all 12 volt power.

Reply #10
Sure is relieving when that's the problem.
Dub McBride 1996 270

Re: Lost all 12 volt power.

Reply #11
You aren't the first to bump it (or have a pet do so) and not realize it  :whistle: 
I'm actually surprised that it took 5 years to happen for the first time. So I guess I was due. :))
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: Lost all 12 volt power.

Reply #12
It took me 10 years and then about an hour to figure it out.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Lost all 12 volt power.

Reply #13
Here is what I did so our Salesman's switch didn't get tripped accidentally by us or our curious great grandkids.
I don't have a picture of the little PVC end cap that you can buy that covers the PVC end opening. Fits in nicely and looks good, altho one could paint the PVC whatever color they want.
The PVC pipe is glued to the floor with: WHAT ELSE but SHOE GOO!!
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD

Re: Lost all 12 volt power.

Reply #14
How about drilling a 1/4" hole toward the end of the handle, installing a 1/16" screw eye/loop over by the "off" position and then running a tie wrap to secure it in the on position?

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Lost all 12 volt power.

Reply #15
How about drilling a 1/4" hole toward the end of the handle, installing a 1/16" screw eye/loop over by the "off" position and then running a tie wrap to secure it in the on position?

There are times you might want to quickly shut off the 12V - say a safety problem.  Yes, very rare, but...  Wouldn't a tie wrap cause delay while you tried to find something to cut it with?
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Lost all 12 volt power.

Reply #16
Yes, the quarter inch tie wraps are very strong but you can buy 3mm tie wraps with a max strength of 18 lbs. Enough to keep from kicking the switch but a finger can break one. https://lecoplastics.com/tie-wraps.aspx  They are only about 4 inches long so about the right length without cutting the extra.

A mini lobster claw or trigger snap chain fastener would also be an alternative. They don't require much extension before releasing.
Trigger Snaps | Pet Hardware®

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Lost all 12 volt power.

Reply #17
A mini lobster claw or trigger snap chain fastener would also be an alternative. They don't require much extension before releasing.
Trigger Snaps | Pet Hardware®


I like that idea, plus you could add a second eye to lock the OFF position, if you needed a "Lock Out/Tag Out" scenario while working on something connected to the house 12V.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Lost all 12 volt power.

Reply #18

Or replace it with a switch like this that has a removable handle, but then you'd need a place to store the handle.
Amazon.com : Blue Sea System 6005 Battery Switch Mini On/Off (25103) :...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Lost all 12 volt power.

Reply #19
I did the same thing the other day going out of the coach my knee hit the switch and all 12 volt lighting instantly went off. I knew immediately what I did so wasn't a big deal but
Don't think I really would want to lock that switch down anyway or remove the handle. I think it's just good to be aware that if you have problems with 12 volt check that switch first.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Lost all 12 volt power.

Reply #20
Personally, I like that switch and use it often. 

We keep our coach inside in a storage unit, and it's dark in there.  I leave some of the ceiling lights on, and just turn on the switch when I open the door and instantly have light throughout the coach (and some music as I leave the dash radio on my favorite station).  I turn it off when I leave the storage unit.
1996 U295 36' WTBI

 

Re: Lost all 12 volt power.

Reply #21
I think, so far, that my PVC idea is the least "hi-tech" of all the ideas presented here, along with the simplest and quickest way to access and actuate the Salesman's switch.
Now, if I could just come up with a way to signal that the switch--and only the switch-- has been turned to the "OFF" position
Nitehawk,  Demolition Lady, & our NEW master, Zippy the speeding BB cat.
1989 Grand Villa 36' ORED
Oshkosh chassis, 8.2 DD V8
2006 Saturn Vue AWD