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Topic: Auxiliary Compressor and the Ghost (Read 1070 times) previous topic - next topic

Auxiliary Compressor and the Ghost

Why does my aux. compressor come on when the fuse has been pulled? I have noticed this a few times; I have an ON/OFF switch wired in-line with the compressor's fuse (double blade auto type in a rubber fuse holder with a rubber cover) and occasionally the compressor runs even though the switch is OFF. It happened today and I ran out and pulled the fuse from the holder while it was running. It made no difference. The previous owner of this coach told me he thought there was a ghost in it.
Any ideas how this can happen?
Dick, '03 U320 40' Tag, 2 slides, Coach #6075
Full Timers
2009 Honda CR-V

Re: Auxiliary Compressor and the Ghost

Reply #1 –
Quote
Why does my aux. compressor come on when the fuse has been pulled?
Quote
Any ideas how this can happen?

That should be the only source of power coming thru the fuse.
Yes it is a ghost  :o
My compressor always shuts down when I pull the fuse.
Is it possible that the fuse holder is shorted out (a stray wire inside touching both sides of fuse blades) so that the fuse makes no difference.
Just a thought.
Cut one side of wire to fuse holder and that will tell you if the fuse holder is bad.
You have an ON/OFF switch also which makes this pretty much imposable unless the switch is bad or wired wrong also.
Seems unlikely but I have seen stranger things.
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: Auxiliary Compressor and the Ghost

Reply #2 –
a. wrong fuse?
b. dual power supply?
c. fuse line bypassed?

Quote
Barry Beam wrote: 
 
Quote
Why does my aux. compressor come on when the fuse has been pulled?

Any ideas how this can happen?

That should be the only source of power coming thru the fuse.
Yes it is a ghost :o
My compressor always shuts down when I pull the fuse. Is it possible that the fuse holder is shorted out (a stray wire inside touching both sides of fuse blades) so that the fuse makes no difference. Just a thought.
Cut one side of wire to fuse holder and that will tell you if the fuse holder is bad.
You have an ON/OFF switch also which makes this pretty much imposable unless the switch is bad or wired wrong also. Seems unlikely but I have seen stranger things.
 
Barry BEAM #16014
Coach Build # 6024
Villa Park CA 2003 U320 40' AGDS
03 Acura MDX
FORETRAVEL Motorhomes service and Repair Information
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"Whatever the mind can conceive and believe, it can achieve"

The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Auxiliary Compressor and the Ghost

Reply #3 –
Hello: I have a 2002 u-270 with the fuse out. If you try to adjust the air bags(fill) the comp will start running.
John Patrick
2002 U270

Re: Auxiliary Compressor and the Ghost

Reply #4 –
Opelgt327, maybe that is what my system is trying to do sometimes. It is a surprise though. When the comp. is running and I turn the witch off it stops immediately. As Dave suggested there may be a dual power supply.
Dick, '03 U320 40' Tag, 2 slides, Coach #6075
Full Timers
2009 Honda CR-V

Re: Auxiliary Compressor and the Ghost

Reply #5 –
Hello, I feel there is dual circuits with single power.  My air comp. will only come on if I manually try to inflate the air bags, with the fuse pulled the system will not auto start (fill) I have been trying to find a leak in the air system for a few weeks ,my air comp,comes on once an hour to check the status pf the coach, which I believe is correct, but when I remove the fuse it stops and the motorhome still stays level, no air bag loss. but with  the fuse pulled i can manually inflate the air bags. John Patrick..on the road in New Mexico now, thanks for input.. I could always look at the schematic, but that would be too easy and no fun and not nearly as sociable!
John Patrick
2002 U270

Re: Auxiliary Compressor and the Ghost

Reply #6 –
If the most probable solution is not possible then, the solution must be improbable.
There is a defective backflow valve in the pump and that is the reason the system is loosing air.
When any request is made to the system, the remaining air in the system back flows and drives the compressor like a motor and just makes you THINK it is running.  Without an electrical connection, the only thing that could make the pump run, is AIR, eh?
Regards,
JON TWORK KB8RSA
Full Time RVer (10+ Years) & Dedicated Boondocker
Retired, Unemployed, Homeless Transients
1996 Foretravel U270-36 w/24' Timberwolf Trailer
I firmly believe that tomorrow holds the possibility for new technologies, astounding discoveries, and a reprieve from my remaining obligations.
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The Second Amendment is in place in case they ignore the others.

Re: Auxiliary Compressor and the Ghost

Reply #7 –
Quote
I have a 2002 u-270 with the fuse out. If you try to adjust the air bags(fill) the comp will start running.

Well after pulling the fuse and trying to manually level, The compressor did come on to my amazement.
I am surprised that pulling the fuse would not disconnect all of the power.
I have not found this secondary power on the diagram but I am digging into it now.
SOOO maybe there is no ghost  :o
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"