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Topic: Dash AC compressor troubleshooting  (Read 2855 times) previous topic - next topic

Re: Dash AC compressor troubleshooting

Reply #25 –
...and just for learning, what are these square modules with the spades?
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Dash AC compressor troubleshooting

Reply #26 –
Quote from: Michelle –
That looks like the SGM module:

The selected media item is not currently available.
Thanks!

I don't have that in my coach manual, but now I do.  Of course I'll never need it again now that I have it.  :D
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Dash AC compressor troubleshooting

Reply #27 –
I believe those square modules are diodes.

I need to get in on mine and do some parts swapping. I think that three of them are used to control the fan speed and my "Low" setting does not work.

Rich
Rich and Peggy Bowman
2002 U270 3610 WTFS, build #5939--"Freedom"
2022 Jeep Grand Cherokee Summit 4xe
SMI AirForceOne brake system
PakCanoe 15

Re: Dash AC compressor troubleshooting

Reply #28 –
The square 4-post modules are called bridge rectifiers, but they are used as a diode in our application, which is one way to use them.

For your reference, I've attached a picture of that same setup from my coach. 

The relays I mentioned in my previous post are mounted next to the battery isolator by the engine.
Keith
2003 U320 38' #6197

Re: Dash AC compressor troubleshooting

Reply #29 –
Quote from: WS6_Keith –
The square 4-post modules are called bridge rectifiers, but they are used as a diode in our application, which is one way to use them.

For your reference, I've attached a picture of that same setup from my coach. 

The relays I mentioned in my previous post are mounted next to the battery isolator by the engine.
Yours is organized and spaced so much nicer than mine...looks like they got better as time went on.
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Dash AC compressor troubleshooting

Reply #30 –
It was the blue wire and needed to be reconnected to the relay circled in red...but of course it was the spade in back and had to do gymnastics and a long pair of needle nose to slip on...
But air kicks on and was blowing at 40 degrees, hate when I cost myself wasted hours...but I did learn some about how the dash AC works.

Thanks again for everyone who helped.
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Dash AC compressor troubleshooting

Reply #31 –
Congrats on getting it fixed.  I've got to get into mine again as the last time I used it, the fan only had high and low.  Medium ran at the low fan speed, so something's amiss.
Keith
2003 U320 38' #6197

Re: Dash AC compressor troubleshooting

Reply #32 –
Quote from: WS6_Keith –
Congrats on getting it fixed.  I've got to get into mine again as the last time I used it, the fan only had high and low.  Medium ran at the low fan speed, so something's amiss.
Wonder if it's those diodes that were mentioned? It's not fun getting in there so sometimes you have to ask yourself is the juice worth the squeeze.
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Dash AC compressor troubleshooting

Reply #33 –
Quote from: WS6_Keith –
The square 4-post modules are called bridge rectifiers, but they are used as a diode in our application, which is one way to use them.

Your prior post with more info  :)  1995 u295 dash AC not working
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Dash AC compressor troubleshooting

Reply #34 –
Quote from: dlkj07 –
Wonder if it's those diodes that were mentioned? It's not fun getting in there so sometimes you have to ask yourself is the juice worth the squeeze.

There's some prior discussion on the bridge rectifiers for fan speeds  No High Speed Fan on Dash Vent

And WS6_Keith's diagnostic write-up  Intermittent fan motor function

Note that the SGM module schematic I linked earlier is dated 2002.  I believe earlier coaches have a slightly different module since I found a post from 11 years ago about a retrofit/upgrade from SGM.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Dash AC compressor troubleshooting

Reply #35 –
Quote from: Michelle –
There's some prior discussion on the bridge rectifiers for fan speeds  No High Speed Fan on Dash Vent

And WS6_Keith's diagnostic write-up  Intermittent fan motor function

Note that the SGM module schematic I linked earlier is dated 2002.  I believe earlier coaches have a slightly different module since I found a post from 11 years ago about a retrofit/upgrade from SGM.
What does SGM stand for?
Dylan and Aimee
2001 U320 4013
Unit# 5896
450 HP/IFS
 

Re: Dash AC compressor troubleshooting

Reply #36 –
Quote from: Michelle –
Note that the SGM module schematic I linked earlier is dated 2002.  I believe earlier coaches have a slightly different module since I found a post from 11 years ago about a retrofit/upgrade from SGM.

Here's the one that SGM provided me for my 2003. 
Keith
2003 U320 38' #6197