American Coach: American Tradition - A/C Blower

[DeanEWest]

This is my first post on iRV2. My wife and I just survived a harsh case of Covid and while we were in the hospital (we shared an ICU room which we called the Honeymoon Suite), we collectively decided to buy a motorhome. We had not heard the word Coach before until we went to buy one. So with just that statement, it's obvious we know very little about RV's, Coaches, Trailers, etc.

We ended up buying a 2005 American Tradition from a guy in Las Vegas. The owner was terminally ill and in fact, passed away on the day we closed on the motorhome, God Rest his soul. We had done a pre-buy inspection so we thought we knew all that was needed to step into the coach and get started on our first of many adventures.

We were told the A/C blower was in-op and figured how hard could that be? I had read a few posts on this site, groups.io and a few others. From what I read, the symptoms I observed in our coach could be repaired by either the connections within the wiring harness under the entry steps or the fuse behind the dash.

Driving home to Huntington Beach from Las Vegas in August without A/C stressed how important it is to get the dash A/C working as soon as possible. Saying the 116 degree temperature while passing through Baker, CA was a bit uncomfortable is an understatement.

The blower itself had been disassembled by the prior owner. We have no one to explain to us how to reassemble the unit. It appears to be pretty straight forward but a picture depicting how it should look would be helpful. Here are a few pictures, of the bay below the driver's seat, of what it looks like now.

Attachment 343559

Attachment 343560

Attachment 343561

Attachment 343562

There are, of course, other items needing repair, and future items to be found later, which I will post separate from this post but I thought it best to start with one item at a time.

Coming up in the near future will be the inverter/battery charging set up and the resets to get that operating the way is should. Also, the rats next of wires behind the dash (possibly contributing to the A/C Blower situation)

Thanks to all in advance for your help. I'm sure I'll have many posts in the future to talk about, and hopefully, as I learn the nuances of RV ownership, I'll be piping in with many solutions for others on this forum.

Dean West
2005 American Tradition 40W

[Hittntheroad]

First step
Apply 12 volts directly to fan motor to make sure it is good
If good
Test motor leads that go to fan motor when the fan switch is on
There should be a resistor module mounted somewhere in the duct
It will have a 12 volt wire coming to it. The resistor controls the fan speeds. Check for 12 volts to the positive wire there with the switch on.
Go to the fan switch and check voltage there
Just have to keep working backwards
I had a fan motor quit and took 3 days to find the fuse Fleetwood had shoved up under the dash in the wiring harness rat nest.

[mttop]

Welcome to IRV2!

There are really knowledgeable folks on this site and I’m sure you are going to find the help you need.

Good luck with your Coach.

[DeanEWest]

Hello and thank you for the reply.

I hooked up a car battery and the Blower turns with no issues.
I've check a few wires in the blower box (below the hatch below the driver's seat) and no juice with the fan and defroster switches on the dash in the "on" position. There is a cut wire that I'm curious about.
(Pictures showing red wire with blue striping). This wire looks to have a resister encapsulated in, what I would term, a plastic fuse case.

Yes, the rat's nest is daunting. Also, I have brackets and what looks like a CPU completely detached from underneath the dash. I would like to secure everything to its proper place, if I can find the properly place.

Thanks again for your input.

Originally Posted by Hittntheroad

First step
Apply 12 volts directly to fan motor to make sure it is good
If good
Test motor leads that go to fan motor when the fan switch is on
There should be a resistor module mounted somewhere in the duct
It will have a 12 volt wire coming to it. The resistor controls the fan speeds. Check for 12 volts to the positive wire there with the switch on.
Go to the fan switch and check voltage there
Just have to keep working backwards
I had a fan motor quit and took 3 days to find the fuse Fleetwood had shoved up under the dash in the wiring harness rat nest.

[oldnavycdr]

Dean, that looks like a Denso system. There is a manual for it here: https://www.densoheavyduty.com/rv

[DeanEWest]

Thank you.

[Conchasjim]

That looks like a diode. Would need the number on it to be certain. With a meter, put the negative lead on the end with the band. Your looking for less than 100 ohms. Reverse the leads, should read open.

[oceansailor]

Originally Posted by Conchasjim

That looks like a diode. Would need the number on it to be certain. With a meter, put the negative lead on the end with the band. Your looking for less than 100 ohms. Reverse the leads, should read open.

Worth noting: lots of digital VOMs will not read resistance across a diode junction; that's why they often have a separate diode setting. For the meter below, that's the one between the 200Ω symbol and the transistor gain (hFE) positions.

And yeah, that looks like a typical 4007 1A/1000V diode.

[Gary RVRoamer]

Yes, it is a Denso system (just like my 2004).
I had trouble with an intermittent fan relay circuit in mine, but I don't think it was the relay itself (I swapped with another and no change).


I hate to be a Debbie-downer, but it looks like the former owner was a butcher rather than an electrician. Hope he hasn't mucked up too many things. I shudder when I see half-baked mods, cut & dangling wires, and disconnected parts. There is no telling what may have been done!

[gjames50]

This parts catalog has diagrams that will show you how it is assembled. Hope this helps. Look for the section called American Eagle, Dream, Tradition HVAC (2001 and on)

https://www.comfortairgr.com/wp-cont...ts-catalog.pdf

[oldnavycdr]

The diagram shows a 10 amp fuse to the compressor clutch. Anyone know the location of that fuse?

[Genevatexan]

The compressor clutch fuse on our 2007 American Coach tradition 40J is under the entry step in the upper step fuse box near the outboard side of the fuse box turned a different direction than almost all the rest of the fuses. (We are working on a different AC issue and thought to update this old thread to complete the OPs question. )

[jblackfame]

Originally Posted by Hittntheroad

First step
Apply 12 volts directly to fan motor to make sure it is good
If good
Test motor leads that go to fan motor when the fan switch is on
There should be a resistor module mounted somewhere in the duct
It will have a 12 volt wire coming to it. The resistor controls the fan speeds. Check for 12 volts to the positive wire there with the switch on.
Go to the fan switch and check voltage there
Just have to keep working backwards
I had a fan motor quit and took 3 days to find the fuse Fleetwood had shoved up under the dash in the wiring harness rat nest.

The defroster blows but the drivers air doesn't come on no heat or AC. The switch turns but nothing happens. any idea what to do? Camping world doesn't know. 2007 American Tradition 42L

[Genevatexan]

We finally sorted out our dash air fail on our 2007 Teadition 40 J - National I door RV found it- not the clutch fuse , compressor or clutch. It was one of two “modules” behind the dash controls. The one that failed had a relay on it that handed power to the controls - the modules are discontinued circuit boards and National Indoor added a dah switch to work around the problem and everything now works properly - that was the good diagnostic skills of the electrical guy in the Dallas store for National indoor.��