Community Forums

dhaselman · 02-09-2021, 10:00 AM

I a new RV'er that just bought a 2012 Tiffin Allegro 30ga 3 mo ago and this has happened to me twice.
My granddaughter started playing with the switches right inside the door and one disconnects the 12v system. I switched it back on but the 12v did not come on. I finally pulled the 2 fuses by the converter/charger (outside drivers side storage area) to see if they had blown but they didn't. I put them back in and the 12v system came back on inside the coach.
Yesterday I picked up the coach from the shop where I was having the tow bars installed over the last week and same thing happened. I plugged in my electric hookup back at the site but the 12v system did not come on. I pulled the fuses and reinserted them and the 12v system came on.
Any clues on what I'm doing wrong or where I should look for troubleshooting??

Thanks,
Dave

garykk · 02-09-2021, 02:56 PM

That switch near the door is called the salesman switch. It operates a 12 volt solenoid and it sounds like it’s acting up. It’s usually near the battery compartment where the large fuses and switch are on some model.
It also could be the switch itself that is acting up. It pops out of that panel with a little care. You could test the switch by jumping the switch

Reacher · 02-09-2021, 03:00 PM

Check the inverter/charger system, settings and circuit breakers.

**Lt Dan** · 02-09-2021, 03:32 PM

As Gary indicated, it's a common problem for the main power solenoid to act up. It's a specialized solenoid called a latching relay. It does not stay powered all the time like a regular relay. Momentary power in one direction turns it on and in the other direction turns it off.

twinboat · 02-09-2021, 03:48 PM

You say you plugged in to shore power but your 12 volt system didn't come on.

Why was it off ?
Had you switched it off ?
Does it go off when you pull the plug ?

Unless you turn off the labeled " Battery Disconnect " switch, near the door, the 12 volt system should have stayed on, running on the batteries.

Pulling and installing converter fuses will not do anything to the Battery Disconnect. Its locked on or off until its touched again.

You need to look over all of the battery cables for loose or dirty connections. Possable dead batteries.

The granddaughter thing was a coincidence.

C.Martin · 02-09-2021, 04:26 PM

The house disconnect relay is normally a latching relay...meaning it only takes power to switch it...once it is ON or OFF..it doesn’t require power. There should be a fuse on constant battery power somewhere that powers the Switch/Relay. I might baby proof it by pulling the fuse when my GrandDaughter visits. That way you don’t have unexpected accidental outages.

The switch should immediately restore 12vdc. I would check the House battery...it almost sounds like the converter is doing all the work. Your coach should be able to power the 12v systems off of battery alone...and I haven’t heard or know about any time delays...or computers which need to be rebooted using the fuses you have been pulling. Sorry...that eludes me.

dhaselman · 02-09-2021, 07:23 PM

I checked the charging system before I pulled the fuses and it seems like it was working (the cooling fan was running is as technical as I got before I came to that conclusion) so I'll dig into the relay as it seems like a likely cause since when I pull the fuses something (a stuck relay?) changes state. Thanks for pointing me in the right direction.

dhaselman · 02-09-2021, 07:29 PM

Just reading Twinboat and CMartin posts. Once the 12v power came back on I quickly read the battery voltage and it was at 13.5v, which I took as ok but given the poor maintenance on the other items I have had to service from the previous owner I will test the batteries before the relay change out. Thanks!

C.Martin · 02-09-2021, 07:58 PM

Quote:

Originally Posted by dhaselman

Just reading Twinboat and CMartin posts. Once the 12v power came back on I quickly read the battery voltage and it was at 13.5v, which I took as ok but given the poor maintenance on the other items I have had to service from the previous owner I will test the batteries before the relay change out. Thanks!

I would check battery voltage with the engine Off, Generator Off, and no shore cord plugged in. This should be the true status of the battery. When the converter kicks in..it has already started charging. Even really good AGM deep cycle batteries only have around 13.0v resting voltage. A used Flooded lead acid will be around 12.6v resting. Seeing 13.5 means you are looking at the converters output going to the battery/12v system.

dhaselman · 02-10-2021, 04:37 PM

One last post - I switched out the batteries and that did not cure the problem. I think it definitely contributed to it as the age was undetermined and they did not test out but the relay was also bad. Thanks for all your help!!