House battery switch diagnosis

Joshua · 06-13-2020, 03:09 PM

Inherited this 30' 2000 minnie winnie on ford chassis. Have always used shore power but prepping for a remote camping trip. Have read the owners manual.

The house lights and power only work if i hold the auxiliary power switch "on" next to the door. The solenoid activates. Once i remove my finger the solenoid deactivates.

Batteries are in good charged condition.

Solenoid is in working condition.

The switch appears to be factory issue and is s momentary on/neutral/off switch.

I was thinking maybe it should be a on/off switch but then considered there might be some kind of protection circuit that is causing the power to switch off? Any ideas?

Morich · 06-13-2020, 03:54 PM

Several different things to check. One is to look for some switch to cut off the coach batteries during storage, etc. This is an easy thing to miss and easy to fix at times.
But assuming not that, some thoughts on the Aux or boost switch. I think of it as a temporary jumper cable to just start the engine in case the start battery is down so we can combine coach and start battery to get enough power to crank the engine.
But I think there is confusion about the switch due to location. I suspect the one near the door is actually the coach battery disconnect and should be left on when inside power is wanted. Hard to reach that location from the drivers seat to jump start, right? so look for second "jump start" switch near the dash and driver.
So what I think I'm reading is that holding the switch makes the solenoid pull up and you are getting power for the inside lights coming from the start engine being connected temporarily to the coach battery string.
If one has a helper push the switch while you feel the solenoid, you can often feel the "clunk" of it pulling up the contacts but it's temp!
This solenoid should also pull up (feel the clunk?) when the engine is running so that both batteries are connected together and will get some charge from the engine alternator as you drive.
But both strings of batteries need to be charged and it is easy to miss that they are two seperate strings, if one is not used to looking at RV.
Suggest make sure both battery strings are charged, switch at door is on and then see how things look.
Let us know what it looks like as this is a pretty common problem but takes lots of different twists and turns to sort out due to different years makes and models.
There are actually two different models of 30 footers for that year!
Wf430V and WF430 V DL so a look at the specs page possibly under the drivers window may pin it down further if diagrams are needed.
Possible it is item 7 on page 42 of this list?
http://www.winnebagoind.com/service/...00/0wf430v.pdf

Joshua · 06-13-2020, 04:41 PM

Thanks for the detailed reply.

The model is wf331c.

The aux start or boost switch is on the dash near parking break release. That is not at issue.

The main disconnect for the coach batteries is called the auxiliary battery. This switch is in the coach near the door. This is where my issue lies. I can only power the coach if i hold this switch 'on' but it is a momentary switch meaning it's designed to click on then reset to it's neutral position. Same thing if rocked to off. Im assuming there is a circuit or system that takes this switch input and there is some kind of logic that is causing the solenoid to be deactivated this turning power off to the coach. Unfortunately my voltmeter broke a while ago and i have not replaced it so detailing my diagnosis is proving somewhat challenging.

BobC · 06-13-2020, 05:02 PM

You are correct and have the right switch. For what it's worth, I found a post addressing the opposite problem. Some of the comments may help you, especially post #11 that refers to a PDF that may be of some help. Note that low battery voltage can also be a culprit.

Morich · 06-13-2020, 06:39 PM

Quote:

Originally Posted by Joshua

Thanks for the detailed reply.

The model is wf331c.

The aux start or boost switch is on the dash near parking break release. That is not at issue.

The main disconnect for the coach batteries is called the auxiliary battery. This switch is in the coach near the door. This is where my issue lies. I can only power the coach if i hold this switch 'on' but it is a momentary switch meaning it's designed to click on then reset to it's neutral position. Same thing if rocked to off. Im assuming there is a circuit or system that takes this switch input and there is some kind of logic that is causing the solenoid to be deactivated this turning power off to the coach. Unfortunately my voltmeter broke a while ago and i have not replaced it so detailing my diagnosis is proving somewhat challenging.

Okay ,a momentary switch would seem to indicate there is a relay at some point which should lock up on it's own current to stay after the momentary is released.
Did Bob maybe fail to get the link posted? It sounds like he might have good info.
Winnebago does a great job of posting wiring and drawings for things like this but it takes lots of practice to read them at times.
I cut a snip of the drawing that is found here:
http://www.winnebagoind.com/diagram/2000/132245.pdf
Marked up how the power gets from battery to the relay and it seems to give locations, so maybe some help on locating those?
Is the solenoid a stranger to you or used to looking at them? I normally expect the small wires to get power or a "signal" that makes the solenoid pull up to put he battery directly connected to the left post (in the drawing) through to the right big post.
Maybe a start to finding a problem?

BobC · 06-13-2020, 07:30 PM

Quote:

Originally Posted by BobC

You are correct and have the right switch. For what it's worth, I found a post addressing the opposite problem. Some of the comments may help you, especially post #11 that refers to a PDF that may be of some help. Note that low battery voltage can also be a culprit.

Sorry, here's the link:

https://www.winnieowners.com/forums/...ge-357226.html

Morich · 06-13-2020, 08:35 PM

Okay a bit different way of latching using magnet rather than current through it's own coil. Makes more sense than what I was thinking as it does not use battery full time to hold it in closed or open position but simple magnet.
But then if we think the situation through, the OP is getting power to the coach as long as he holds the switch, but with it being a momentary switch, it is designed to give a burst of current and then remove that current when released.
So the big kicker would seem to be that the coil pulls but the magnet doesn't hold it!
That seems to me to put it very much into being a defect in the latching part of that relay which can be much more simple than chasing the path for the current to pull it in the first place.
This latching relay is one that I got some experience with when converting my Focus to tow four wheels down as it has to have the battery disconnected. So we get options for replacing the relay/solenoid.
This is what they installed on my car:
https://www.amazon.com/Roadmaster-76.../dp/B01F8E5CX2
But this appears to be a far better value and more like the original:
https://www.amazon.com/INTELLITEC-01...6595MJVSP6G6FM
A little more shopping may turn up much better pricing, though.

NeilV · 06-24-2020, 08:50 PM

Yes the latching relay is supposed to hold its last set position and operates like a remote operated switch. This is a good thing since a normal relay would have to be energized the entire time to hold the power in the on position adding a constant draw on the batteries. If its not holding once you release the switch its very possible that the latch inside the relay is broken or stuck in the released position.

There should also be a pop-up 30 to 50 amp breaker between the converter and the batteries. If that is popped you will only be able to power the lights from the converter and the batteries will only be getting charged when running the engine.

Note that in that year the converter only charges the house batteries and not the engine battery so be careful about running the in-dash radio without switching its power switch to the house battery position or running other accessories powered by the engine battery or you may find yourself needing to use the auxiliary battery switch to get the engine started.

pkthoegersen · 06-24-2020, 09:49 PM

This is the solenoid that you probably have. Your momentary switch will energize the white and ground the brown in one direction and reverse polarity in the other direction if the solenoid doesn't make the "switch over" its junk

youracman · 06-25-2020, 11:31 AM

I have a 331C also......just 7 yrs newer but likely not much different.

Here's another picture of the latching solenoid which I replaced at 10 yrs of use (I have noted a lot of posts over the years re this solenoid and they seem prone to failure at 10 yrs and beyond so I did a "preemptive strike" on it.) You may have to click on the pic to enlarge it.......if needed.

Amazon has a lot of them in different styles, but I got mine from Lichtsinn RV so I could be assured that the mounting holes would line up, etc. If you call them, have your WBGO S/N handy (not the VIN) and you will get an exact replacement. 1-800-343-6255

Good luck with the fix, and safe travels.

Joshua · 07-13-2020, 10:26 AM

Thanks for the detailed replies!

The issue ended up being the switch. Internally one of the contacts corroded. Luckily i was able to take it apart and clean it. In the process of diagnosing the issue i took apart the solenoid and cleaned it as well.

For anyone finding this thread in the future, dont be like me and hold the power switch on to use power. It drains your batteries really fast and isn't good for your solenoid!

Morich · 07-13-2020, 10:42 AM

Quote:

Originally Posted by Joshua

Thanks for the detailed replies!

The issue ended up being the switch. Internally one of the contacts corroded. Luckily i was able to take it apart and clean it. In the process of diagnosing the issue i took apart the solenoid and cleaned it as well.

For anyone finding this thread in the future, dont be like me and hold the power switch on to use power. It drains your batteries really fast and isn't good for your solenoid!

Interested in the mention of taking this solenoid apart. Mine is buried behind a breaker panel where just getting a look is difficult, so I have not got really seen how it is made.
What did it take to get it open? Some require total destruction to get a look inside!

Joshua · 07-14-2020, 12:13 AM

Some solenoids are serviceable. Mine had 4x Philips screws holding it together. Take apart, sand contacts, rinse with cleaner and put back together.

Bones2003 · 07-14-2020, 09:45 AM

Joshua, you might want to consider purchasing a new switch and solenoid to keep on-hand as an insurance policy. Sanding contacts is generally considered to be a temporary fix as it can remove the high current/low resistance plating from the contacts.

Morich · 07-14-2020, 11:07 AM

Quote:

Originally Posted by Joshua

Some solenoids are serviceable. Mine had 4x Philips screws holding it together. Take apart, sand contacts, rinse with cleaner and put back together.

Thanks for the insight as I can't see mine well enough to spot those details. Hoping to never need the info is kind of like hoping a virus doesn't spread. It seems to encourage the gremlins!