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Topic: Stumped on a 12V problem (Read 617 times) previous topic - next topic

Stumped on a 12V problem

I just replaced the original Fantastic Vent Fan in my U280.  My problem is the 12V+ wire that comes through the box beam fan frame from drivers' side for the fan is dead.  It is virtually impossible to trace.  I have been unable to find where it splits off from 12V wire loom under the sink.  The vanity light power wire splits off under the sink to light switch by toilet and then the outbound power to vanity lights goes down via the same path, heads aft under the shower to then go up into the ceiling and back to lights each side of mirror.  There is only one 14 ga wire( blue) attached to fuse block.  If I can't find where the fan supply wire is bad, I'm thinking I will splice into vanity light power before the light switch and fish wire up to wire in the fan.  According to electrical diagram, load should be about 8.69 amps.  Looking for comments and or where did they split the fan wire off the loom?

Thanks in advance.

jk
Jack and Cathy
1992 U280 Unihome 36' Build #4034
Cummins 8.3 /  Allison MT647/ PacBrake
Apopka, FL / Barre Center, NY

Re: Stumped on a 12V problem

Reply #1 –
On our U225 the fan has no power until you open  the vent. There is a safety lock/switch on it.
1992 U225 36'
Build #4134
1987 Rockwood 32'
Ham radio/Motorcycles and old cars
Both of us are Retired
Married 32 years
Other half is "Old Toolmaker"
Dog named Duke.

Re: Stumped on a 12V problem

Reply #2 –
If you can find a 12v wire that is live, then go pull cb's to see what circuit it is on.  Check that you will not overload that circuit, also check to see if it is on the salesman switch at the door.  That switch turns off a lot of stuff, but not the refrig and some alarms.  Might be possible to use the old dead wire to pull in a new wire if you can find the other end.  The salesman switch is on, right.
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: Stumped on a 12V problem

Reply #3 –
Kimo,  maybe your old fan didn't work (assumption) because of no power coming in through that wire?

Re: Stumped on a 12V problem

Reply #4 –
Pull house fuses power back through that wire with another battery and see if you can find which wire.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: Stumped on a 12V problem

Reply #5 –
Quote from: Travelin' Man –
Kimo,  maybe your old fan didn't work (assumption) because of no power coming in through that wire?

Yes.  That's correct.  The fan was original and it was due for replacement.  I have used a wire chaser and have been unable to locate the suspect wire in the loom.  I can trace it from outside of coach down the outside wall but can't locate it after it runs "north and south".  Since only one wire leaves the fuse block I have to assume the split it somewhere to run from the light switch and the fan. It is not anywhere near the light switch for sure.  I suppose someone may have rewired it in the past from another source so I will try to employ Jerry's idea and see if it shows on another fuse line.  I'll search some more before employing plan "B".  Thanks.

jk

Jack and Cathy
1992 U280 Unihome 36' Build #4034
Cummins 8.3 /  Allison MT647/ PacBrake
Apopka, FL / Barre Center, NY
 

Re: Stumped on a 12V problem

Reply #6 –
Case closed.  Plan B initiated and completed.  Not ideal but functional.  On to the next task:  Hydraulic filters/oil change.

jk
Jack and Cathy
1992 U280 Unihome 36' Build #4034
Cummins 8.3 /  Allison MT647/ PacBrake
Apopka, FL / Barre Center, NY