2022 Winnebago 29B Radio Switch Loses Power in Drive Mode

[MattRV]

I’m having problems with the dashboard radio switch in my 22 Winnie Adventurer 29B. The radio only works when the switch is in the down position (ie running off the house battery). When I flip the switch up to the drive position the radio dies even with the engine running. I’ve tested everything with a voltmeter. The issue is that the yellow wire (which is supposed to be directly connect to the battery) is only powered when the radio switch is in the down position. It’s supposed to get power all the time so the memory is saved. I’ve checked every fuse and also replaced the switch itself. Now every time I turn off the radio I have to reprogram every preset which is annoying. The alternative is to keep the radio switch down (ie powered by the house) all the time but that leaves the radio powered on. I’m concerned about draining the house batteries. Any ideas?

 

[Bnystrom]

Have there been any modifications to the electrical system or is is factory stock?
When I upgraded our in-dash unit and made other electrical upgrades, one of the consequences was that I lost the ability to power the in-dash unit with the house batteries. We just use the one in the coach instead.

 

[MattRV]

It’s stock. Original wiring. I’m considering just running a wire from the chassis battery to the radio to keep the presets.

 

[Bnystrom]

That being the case, you seem to have covered all the bases in troubleshooting.

Have you tried tracing the wiring back to the main plug and disconnecting/reconnecting it? Also, check for pins that may have backed out.

Has it ever worked as intended? It almost seems like the switch is functioning in reverse.

Worst case, do what you're thinking of and insert a small fuse in the line, just in case.

 

[MattRV]

I bought it used with 10K miles on it so I don’t know if anything was done by the prior owner but from what I can see everything looks original. I’ve replaced the switch. Every connection I can see looks solid. There may be a broken wire or switch buried somewhere. The Occam’s razor solution is to run a wire with a fuse as you stated. Thanks again for the reply.

Does anyone else have input?

 

[Morich]

Have you been able to pull the dash switch to check wiring there?
they no longer are posting the actual 12VDc wiring schematics so we are limited toguessing how things like this are built. As they are going through the drawings and switching to far less useful info we are gradually losing the info we need to be able to sort trouble with any real good plan!
But if you are able to get the dash switch out, there may be some ideas that help?
I have not looked at one anywhere near the 2022 year model but I might guess the switch will have six lugs on the back for choosing which power. The center two lugs would be expected to go to the radio, with one set of outer lugs feeding power from coach and the other from the chassis.
What I expect to find is a switch that connects battery and ground from the coach on one set of two outer lugs to the center pair, then when we flip the switch the other way, those two center lugs get connected to the second set of outer lugs. Double pole, double throw (DPDT) meaning two lugs (poles) can be thrown two directions?
If you can get the switch out to access the lugs, I might suggest looking for battery and ground from the coach on one set of two lugs as it seems to work.
Then when that is ID'd, look at the other end of the switch for the other two outer lugs for battery and ground from the chassis?

This IS getting pretty deep in guessing without having actual info to follow, so be aware of flaws in the plan?? Theory based on the way I have seen it done in other places?
But what sounds correct is that you have battery and ground getting from coach to outer lugs and then the switch connects it through to center lugs to saend on to radio!
The fault may be in the switch not connected it through when flipped (defectiver switch?) OR the feed bring power from chassis battery point to switch may have a problem.
If you find the Winnebago wires have ID stamped as the last 2-3 letters in a long chain on the wires, it may be possible to look up that ID on this list to find the "from" and "to" of that wire.That can lead to knowing if it is battery or ground?

https://www.winnebago.com/Files/Files/Winnebago/Resources/Diagram/electrical_guide.pdf

Something like this could help to sort?

Shows wire LS is 12 gauge yellow wire feeding coach power? But where is chassis and is it labeled for ID?
Is it switch defective or is it a chassis problem as simple as a fuse tripped in some spot we have not looked?
Possibly checking any fuse box where you have chassis fuses might lead to finding one blown as the more quick and easy thought?
Got any drawings on hand for chassis info in the big bag of info? Maybe a handy label inside a fuse box under the hood?

Lacking info it is getting very hard to solve some of these questions and they are going through the online drawings and reducing the help we have had in the past!

Wish you luck on the chase!

 

[Bnystrom]

It just occurred to me that the constant 12v lead for preserving the memory should not be connected to the switch, as the power should be provided from the chassis battery regardless of where the power for the rest of the in-dash unit comes from. It seems like it's wired wrong somewhere. If you can find a pin-out for the in-dash unit, it should show you which lead is supposed to be connected to constant 12v. You can trace that to the connection to the Winnebago wiring and check for voltage.

 

[Morich]

The pinout info for the radio is still posted by Winn but it is now in such degraded fashion that it is no longer usable in any way that I can see. They seem to be gradually moving totally away from one of the things which had made me a firm backer of the brand!
This is what we now have for radio info?

It now shows a fuse at the rear of the radio but without ID on any wires, only that the is a 12pin plug among others? Not somthing I see any value in knowing without knowing WHICH wire or even if it is this plug or one of the other two that seem to be options .

If I were a current Winnebago owner, I would try to salvage all the drawings info I can still find as it seems to be going aways!

 

[Bnystrom]

That really sucks. However, I was able to get a usable pinout from the Sony manual, assuming that the model number in the pic above is correct:

https://www.sony.com/electronics/support/mobile-cd-players-digital-media-players-xav-series/xav-ax3000/manuals

If the in-dash unit is a different model, searching for it online usually gets you what you need.

 

[MattRV]

Very helpful both of you. It's actually an 8-pole switch. The part number is 145638-20-CHT. I've attached a screenshot from the Cortana 3-D portal. The factory sent a new switch which I installed and that doesn't solve the problem.

I've checked all of the fuses under the hood, the fuse on the radio (it shouldn't be that since the radio works), and the fuses underneath the steering wheel (which are extremely hard to get to!).

I also looked at the pinout on the radio. There are 2 wires that matter - yellow (battery) and red (accessory). I think I have isolated the problem to the yellow battery wire (memory). In the standard installation (like in a car) yellow is supposed to be directly connected to 12V from the battery to keep the memory. The radio turns on when the when the red ACC wire is hot. My guess is that Winnebago tried to be "helpful" by putting this switch in the way so that you can run the radio off house power alone with the switch down (down/"house" position), or have it act like a normal car radio that turns on and off with the accessory key (up/"drive" position).

I've noticed that in the "switch down" position there is 12V at the accessory (red) feed into the radio which tells me they are tricking the radio to think the key is on. The problem seems to be that the yellow (battery) feed is only hot with the switch in the down position. When you flip it up to the "drive" position, the yellow wire goes dead. I was hoping it was just the switch but now I know that not to be the case. The wiring chart Morich provided actually has a reference to "Radio Power Switch to Radio (memory feed)" on PP 10. It's labeled "GT/16 YEL". I'll trace that wire when I'm back in the RV this weekend.

The only thing I can think of is that is was either mis-wired at the factory or there's some loose connection/broken wire between the chassis battery and the back of the switch or between the switch and the radio.

If I can't find the problem, I'll just McGuyver (McGruber?) the thing and run 12V from the chassis battery to the yellow wire with a fuse and just pull the fuse when I put into cold storage in the winter so I don't drain the battery keeping the presets.

If anything I've shared above helps diagnose this please let me know. Thanks for the help!

Matt

 

[Morich]

Small point if not clear about the wire ID? The id is GT and then the 16 yellow is the gauge being 16 and color yellow.
so the normal thing (if there is one?) is you should not know that 16 gauge yellow wire at teh switch should have the second end at the radio where you can then be helped a bit by looking for a 16 gauge yellow wire and should be able to then verify being correct by finding the GT id on the wire?
Reason for this is how oftn we get plugs which may have lots of different colors and different gauges but the one you want is one of the smaller and yellow!
My real complaint is that we are no longer getting an actual drawing where we could spend the day tracing the wiring on the drawing before going out in the cold and looking for wire size, color, and ID that we may not be able to read!
When you get around to looking at actual wires, there are likely to be a long string of info but the ID you want is at the last few letters of that string.

Okay on the 8 poles as I had been thinking only of ne function and 8 likely means you are switching more than one circuit at one time when moving it. No chance of a drawing on the side of the switch that shows which lugs connect to which?
If there is a brand and model number, it is possible to go to some site like carling if that brand and find how the lugs connect.
Not a AM-FM radio guy so little idea of how they work them for the preset to keep them alive but power has to go in one lug and out another. The problem being finding which in and which out! Once we can get that checked as getting through the switch, then we need to move to the other end of that specific wire and make sure it gets into the radio or at least the first plug!
The big flaw is finding the info and then we may chase the problem all the way to find the last plug has one wire that backsed out in some way!

I guess we can always fall back on the old excuse? If it was easy they would have somebody else fix it!

 

[Morich]

you are getting info that I have not found but in looking at your picture I did a search using one form of AI (copilot?) that I have been playing with and get this as part of the response:

I have been getting a few really good ideas for help on weird stuff and possibly this would lead to a Carling switch, etc. that we could then look for info on how the contact meet to connect inside?

 

[MattRV]

See below

 

[MattRV]

Here’s what I figured out about the switch. It functions like a normal 6 pole DPDT switch. The top additional two lugs are for the light. What I don’t yet know is how the wires go from the switch to the radio. They run back into a large bundle behind the dash and then there’s a small bundle that runs out the top to the radio. Next step is to use the continuity tester to trace the wires.

 

[Morich]

Sounds like you are well on the way and I might just add confusion, so I'll stand back a bit and watch???
Nothing better than help but also nothing worse than help when not needed!
Always interested but not much more to offer from what you've found!
Good luck !

 

[Bnystrom]

Here’s what I figured out about the switch. It functions like a normal 6 pole DPDT switch. The top additional two lugs are for the light. What I don’t yet know is how the wires go from the switch to the radio. They run back into a large bundle behind the dash and then there’s a small bundle that runs out the top to the radio. Next step is to use the continuity tester to trace the wires.

That's why my switch no longer works after changing the in-dash unit. After spending a lot of time wiring the new one and getting the camera to work, I was up against a deadline - leaving on a trip - and didn't have the time to go digging into those wire bundles. We're now a couple of years without it and frankly, we haven't missed it. At this point, the only reason to dive back into it would be for the satisfaction of getting it to work.

 

[MattRV]

Thanks BNystrom - so do you have the radio wired directly to the chassis battery or the house battery? In either case does it drain the battery over time or is the draw low enough. I do have the solar panel on this vehicle so I would think that would be enough to counteract the draw from the memory saver which has to be very low.

 

[Morich]

I have not seen the need to have the radio wired to the chassis for a couple reasons. One big one is that we never listen to the radio when the engine is not running or we are camped. So if the radio is only used when chassis is feeding coach or coach is fed by cord, we do not worry that power is coming off the coach battery.
but the question of how much drain the presets make is not much and other things are likely working to run the chassis battery down while stored, so we have to assume keeping the chassis charged will not be changed much be adding the radio presets.

One of the big misses for new owners is that they can plug into power but forget that power doesn't normally get to the chassis battery if they do not make special moves to get it there! Some of the older RV were built or had an item called Amp-L- Start or one of the versions but that company appears to have folded and I would assume most RV never got that mod.
That leaves most RV needing some form of charge to keep from finding a dead chassis battery after stored, even for a month.
The thing that misleads many is how we don't put a charger on our cars, so why on the RV? The difference in many cases is that we drive the drive at least nce a week and top off the battery charge. But most do have small drains for things like radio preset or door locks, etc. and will go down if not driven frequently. One of the things folks found when work from home came around!
More electronic gizmos, means more and deeper thinking to keep it all running!

In my last RV, the two battery groups were alongside each other and it was simple to just add a strap between positive postson each as we stored the RV plugged in here at the house. Since they were both lead acid and I had to check the water, putting the strap on was not big thing.
Some have tried wedging something in to hold the boost switch but that tends to reguire power to hold the solenoid and did not seem right for me.

 

[Bnystrom]

Thanks BNystrom - so do you have the radio wired directly to the chassis battery or the house battery? In either case does it drain the battery over time or is the draw low enough. I do have the solar panel on this vehicle so I would think that would be enough to counteract the draw from the memory saver which has to be very low.

It's wired with constant 12v on the yellow lead for the memory, and "key-on" power to the red lead, as is the norm. I've had several instances where it has sat for over a month without being driven and the battery is still fine. I do have a trickle charger (installed by a previous owner) that's wired into the shore power circuit, so I can plug it in periodically during storage to top off the battery. I've only done that a couple of times this winter. All that said, my understanding is that newer models may have more parasitic loads than our 2010 RV/2008 chassis rig.

You solar system is probably set up to charge the house batteries only, unless a trickle charging system for the chassis battery has been added. One simple option - assuming that your rig is stored outside - it a solar panel that attaches to the inside of the windshield and plugs into the cigarette lighter or accessory outlet. They're inexpensive and it's likely all you need.

 

[Morich]

I llike to keep equipment needs to a minimum if practical. So if the solar is good for charging the coach, adding the small amount the chassis may need is one I would guess good to also piggie back on the same by adding a strap at any point where you have hot chassis power to any point where you have hot coach power.
One point that I am sure you have power from each group is the compartment nearly under the driver seat but outside door?
One way to make this handy but require some care with remembering to disconnect the strap when using the RV, is at the connections in that compartment.
You have the newer version of what used to be called a "mode solenoid".
The new solid state that you have is called a BIM but does the same. When the engine runs the BIM connects a big lug on one side to the big lug one the other side to charge the coach as well as the chassis batteries as we drive.
If yo found a handy place to add a small toggle switch connected between coach and chassis battery cables at the bim and placed the toggle somewher ehandy to reach but avoid bumping, you would then have options!
Something like this to keep them connected after driving home to let solar charge both?

You drive it home and they are connected all that time, so when you store, the voltages are very close, so small wires are good for small current, so any place out of the way but handy to flip on while stored and then always remember to open to avoid running both down while dry camped?