One Entire 12VDC circuit dead, but fuse is not blown brand new 2018 FC20

[Wskcondor]

New Years Eve.
On first real camping trip with new trailer.
I had already checked out all the systems last month when I picked it up. Now I am on a camping trip and in the morning of day 2, all is well.
In the afternoon, I go to turn on the forward Fantastic Fan....dead. No response at all (but it was working this morning...). Check the aft Fantastic Fan - works 4.0. Swap local fan fuses (the glass ones) Aft still works on either fuse, forward does not work. (So it isn’t the fantastic fan fuse)

-Decide to take a shower, push up the little round vent fan in the bathroom and....switch does not work. No fan.
-try to turn on furnace to heat up trailer for the shower and...there is now no 12V power to the Dometic control unit (the all in one that does furnace, A/C, fans, heat pump etc). Completely dark.

OK, I am an electical engineer by training, so i understand a little about V=IR, etc.

Called the roadside assistance (1 year free from Airstream I guess) and of course, they are doing the best they can but...have no idea what to do and no suggestions other than, “perhaps you can get a space heater for this trip”.

I was GOING to write this thread and ask for help...but now I think it is more informative, because 10 minutes ago, my girlfriend was taking a shower and not happy that the brand new Airstream has no furnace or heat-and she slammed the medicine cabinet door and....voila, the fan in bathroom came on, the forward Fantastic Fan began working again, and the furnace thermostat regained power AND began properly heating.

Her new callsign is Fonzie.

More importantly...I guess I MUST have poor workmanship behind the thermostat wall/behind the medicine cab.

If anyone has seen this please let me know.

In the space of typing all of those items stopped again, and “fonzie” brusquely shut the medicine cabinet and they are all working again.

This is not how I imagined a 2018 Flying Cloud 20 listing at over $72,000.00 was supposed to work. I thought they were a little more refined and a bit less like “projects”. BUt I am happpy with a lot of the stuff don’t get me wrong.

Any thoughts on how to proceed? Anyone with actual wiring pictures or diagrams? It seeems to me that they have +12VDC coming from the panel, into the wall with the thermostat, then perhaps they put an electrician nut on three wires (Bathroom fan, Thermostat, Fantastic Fan), and it is loose, and the hot wire is falling out.

Any Ideas would be great. It is cold tonight.

V/R,
HAPPY NEW YEAR’S EVE!
Bill

[mimiandrews]

If the problem responds to "impact therapy" I'd guess that you have a loose connection of some kind. Per code, the connection should be in a box. Is there a junction box anywhere near the "impact"?

Of course, power down the circuit while you explore. 12v DC won't shock you, but it can start a heck of a fire.

[A W Warn]

I suggest that you look at that specific circuit's wire connection inside of the converter. I suspect someone forgot to tighten the screw that clamps that wire. Or, the fuse might not be pushed in firmly.

[Wskcondor]

First, thank you for the replies.
- Of course, the first thing I did was check the fuse and tried swapping-that isn’t it. Plus, the connection for the fuses is tight-it would be hard for it to be in there at all without it being connected-they’re very tight and hard to pull out or push in (this may be different for older models, but for my brand new 2018 that’s the way it is).

-I removed the vanity which is the item that was slammed and “made everything work again”, and there are wire bundles back there running up to the ceiling, and down of course, to the road side of the vanity. I tried turning on the little bathroom fan and then by hand “wiggling” the two bundles, to see if I could get them to disconnect again (i.e. make the fan stop). No luck. Fan working 100%.

-Although I removed the faceplate of the circuit breaker/fuse box, I was squeamish about trying to remove the entire converter unit. The main thick 12V wires which are obvious in front-they are well laid out and have the screw-tight terminals-they are all secure.

OK, so what DID I find? Only ONE oddity:
-when I looked behind the vanity, I could of course see the backside of the central thermostat. I observed the phone-jack connector that goes into the back of the Dometic thermostat unit and I pushed it with my finger -and it “clicked”. I.e., it seemed like it was not COMPLETELY clicked into place but it is now.

Q: Does anyone know, are multiple 12V circuits (specifically the forward fantastic fan and the bathroom small vent van) somehow dependent upon operation of the central thermostat? Like perhaps through a relay?

It’s the only thing I can even imagine at this point. Keep in mind when I took delivery 7 weeks ago, everything worked and continued to function up until that camping trip on New Year’s Eve (and since slamming the vanity that same night).
If it had been a loose wire on that circuit that GROUNDED the 12V, it would have blown the fuse, but it didn’t. If it were a loose wire that was going to OPEN, it would have to be a wire prior to branching out to the two fans and the thermostat control (and why would that be all the way in the wall between the dinette and bathroom? - and it would not have been built to code if that wasn’t in a junction box).

I will report if I find anything else but it really bothers me that I could not (yet) find a smoking gun. And I again ask if anyone knows how Airstream wires such circuits, I will buy you a cold beverage for such information.

V/R,
Bill

[Trailbob]

Sorry to hear about your first camping trip.

Not sure if this will help, but I remember watching a video one time where they describe how an Airstream is wired. Might have been on Youtube. I seem to remember there was a large 12v connector behind the vanity in the bathroom that connects several circuits. Something like a wiring loom connector you would find in a car. I don't have any first hand experience with it, but it might be something to research or look further into.

Good luck and please post back whatever you find out.

[Al and Missy]

While 120v connections are required by NEC to be accessible and in a box, I'm not sure there is an equivalent rule for low voltage. I like Trailbob's suggestion. Look in the vicinity of the vanity for a connector that might not be seated well. The various harnesses, side, roof, etc are joined by multipin connectors.

Al

[Paprika]

For what it's worth, Bill, I'm 99% certain the thermostat has no control over Fan-Tastic or bathroom vent fans. Wish I could shed more light on your problem. It's got to be a loose connection, but where? One thought occurs to me: at least in my 2017 International, there's a 12V ground busbar in an outside storage compartment near the inverter, and also a bunch of chassis grounds screwed to the frame underneath that general area. You might want to check those locations for loose ground connections.

By the way, you might want to download a copy of Airstream's parts book for your rig, just for general reference.

It's so frustrating to spend $70K+ and have to deal with this kind of thing. (I had plenty of sloppy workmanship issues with my 2017 International.) Please let us know what you find out!

[AirstreamInc]

Wskcondor,

Congratulations on your new Airstream and sorry to learn about some of the issues you mentioned in your post.

Please feel free to send us a private message or reach out to our customer service and technical support team at*1 (877) 596-6111, option 2 if you need additional assistance.

Thanks.

[DRPREECE]

I experienced a similar issue with our 2017 FC 26U. During winterizing I “rearranged” the bundle of wire in the equipment compartment under the wardrobe and lost 12v power to the forward half of the trailer. Traced it down to a bad crimp and solder job on a single pin in a 12 v cable plug connector.

It appears AS subs out the manufacture of the 12 v wiring harness and it is sized to be used in several models, with significant extra cable being shoved into wherever it will fit.

Luckily I have quite a bit of experience troubleshooting wiring and connectors, along with the tools to make the repairs. Took two hours to find the true cause and 5 minutes to fix it.

AS probably has little if any QA/QC on receiving the cable subassembly and the bad crimp and solder job would have only been found if stressed. Sounds like you may have a similar situation.

[OTRA15]

Great comment DRPREECE!

AS QC has gone down.

[Wskcondor]

Thanks again for the replies. I will write a detailed description to Airstream INc, and I have relayed all this to my dealer.
THis weekend I will:

-look for a bus bar for the ground (I think)
-start thinking about next steps.

I think DRPREECE has probably stated what the issue is-a shoddy crimp job in a harness. But finding where it comes together is my problem. I don’t want to take an entire wall apart in the trailer that is 6 weeks old. Unfortunately the official service folks-I know they are busy with problems they can see and repair, and that are bringing in $$ because they are not under warranty - well, I am getting the shoulder shrug. If it isn’t doing it when they observe it, they aren’t going to go exploring.
They don’t have to camp in it and suddenly randomly not be able to turn on any environmental controls though...

Busy first week back to work so, Like I said, I will work on this hopefully this weekend and see what I can find.

V/R,
Bill

[DRPREECE]

Originally Posted by Wskcondor

Thanks again for the replies. I will write a detailed description to Airstream INc, and I have relayed all this to my dealer.

THis weekend I will:



-look for a bus bar for the ground (I think)

-start thinking about next steps.



I think DRPREECE has probably stated what the issue is-a shoddy crimp job in a harness. But finding where it comes together is my problem. I don’t want to take an entire wall apart in the trailer that is 6 weeks old. Unfortunately the official service folks-I know they are busy with problems they can see and repair, and that are bringing in $$ because they are not under warranty - well, I am getting the shoulder shrug. If it isn’t doing it when they observe it, they aren’t going to go exploring.

They don’t have to camp in it and suddenly randomly not be able to turn on any environmental controls though...



Busy first week back to work so, Like I said, I will work on this hopefully this weekend and see what I can find.



V/R,

Bill

The cable harness connections / connectors should hopefully be in an accessible location behind a removable panel. I would hope AS wouldn’t put anything other than an end point connection in a wall. Hope being the operative word.

Good luck!

[Wskcondor]

I wanted to share a synopsis of my issues and resolutions with the problems I had with my new FC20FB.

AIRSTREAM did one of the posts (you can see above) and that was encouraging-that someone from the company looks through these posts AND actually too action to respond.

I spoke with the dealer that sold it to me, in Portland and they said they would arrange a service appointment with Los Angeles Airstream.

I wouldn’t be doing it right if I weren’t complaining-so I will first give the nit noids of irritation. Keep in mind I am comparing this to other types of service I would expect with an expensive new purchase...
A couple of weeks went by with no return calls, but I was persistent. Eventually it was elevated to my salesperson and a managerial level in service and an appointment was made-arrangements were made-for me to drop off in LA.
[note, this should be easier. Once they have your information it is as simple as a Franklin planner to ensure you give response you promised]

At this time I had the above 12V loose wire issue but also was reading nothing in My black tank, even when it was nearly full. So I had 2 issues I needed them to look at under warranty.

Aaron at LA Airstream was there when I dropped off and was positive about it-seemed like he would not just give it the once over.
I did not hear back after a week, then late in the second week I called (took me a couple tries again, because they did not return my calls). And I got a hold of them.

They said that they “had to do some re-wiring, inside the wall” but felt confident that they DID in fact find a loose crimp or loose wire which would have caused this. I have to take this on faith and everything is working, nothing seems to be intermittent but that is the devil of an intermittent problem...
As for the black tank they said they tested it by filling and it worked 4.0. Not sure how to reconcile this-OR if there is any way the two situations were electrically connected, but...again, only using the camper will tell.

OVERALL, I would give the whole system a “B-“
-Aaron at Los Angeles Airstream would get an “A” for his attitude and helpfulness.
-Los Angeles Airstream overall would get an A-, as they were doing Warranty work for a different sale-but still should return calls, etc. Would have liked a little more written description of the work done, but...still good service and a $0.0 bill
-AIRSTREAM, for the price point, gets a C on this model for workmanship. Hey, they are retailing the 20 foot trailer for well over $70,000. It should be wired correctly. They don’t publish user available schematics to the level I would need to do it myself with harnesses etc, so they should have made it right the first time. This has the highest weighting of my ratings, because it is the company and the company name.
-Portland gets a C+. Too many calls to get one referral and appointment set up. They actually sold me the unit and should have more ownership of that process and sale. A little bit of aggressiveness here goes a LONG way towards customer satisfaction. I do not even care if it is going to take a month, but if the person on the line states that up front, “hey, we are going to take care of you. I promise. With backlogs, and our work and what they have to do in LA, it might take a couple weeks to get set up and a week or two for them to do the work, but we will get it done”. - to me, that is all I need to be happy-honesty and transparency about the process.

In summary, I am happy with the trailer again, and really even with the service. Not over the rainbow ecstatic, but happy. These are expensive units and you should get more if you pay more. I am really happy with the unit itself and functionality and feel and comfort, and I would buy this one again. I would probably do a more grueling wringing out of the unit when I took delivery if I had to do it over again. Not sure all the details of that but perhaps someone should publish a “checklist” for putting it through the paces. I hope this helps others.