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Home » Public Forums » GMCnet » 12V wiring to hall light and bath
12V wiring to hall light and bath [message #117135] Tue, 01 March 2011 19:27 Go to next message
jtblank is currently offline  jtblank   United States
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Well I did it, shorted the mounting screw to the switch connection on the hall light..... snap there went the fuse, checked the bath lights and they came on for an instant and then off. Checked the fuse (OEM setup) and #4 (15amp blown), replaced and still no power to bath or hall fixture. I checked with a meter and have power across all fuses, looking at fuse assignments on the inside of the door #4 is hall light and #5 is bath. Maybe it was wired to #4? Anyway does anyone have schematics on the inside wiring so I know were to chase the open circuit? I'm redoing the headliner and got the back out and was working on removing the short hall piece when all of this started so should help in tracking down the problem. If anyone has any "great" ideas, I'm all ears now that my face is covered in egg admitting the oops! 2 steps forward, 1 step back.

After reading this before posting I still don't understand why the bath light lit for a fraction of a second with the fuse already blown and it's suppose to be on another circuit/fuse???

Thanks


John Blankenship '76 Palm Beach Tulare, CA
Re: 12V wiring to hall light and bath [message #117154 is a reply to message #117135] Tue, 01 March 2011 21:14 Go to previous messageGo to next message
cjonesgo is currently offline  cjonesgo   United States
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I've been working on a "geographic" wiring diagram fro my 76 eleganza. Please keep in mind it is still in progress. I am still adding in the 120ac, but the 12v is basically complete.

The route the wires take probably depends on the individual floor plans, but what is powered by what fuse should be standard. Someone more knowledgeable can chime in on this.

PM me your email address and I can send it over to you. In the meantime, I'll find some place to post it up and link to.



Re: 12V wiring to hall light and bath [message #117156 is a reply to message #117154] Tue, 01 March 2011 21:23 Go to previous messageGo to next message
cjonesgo is currently offline  cjonesgo   United States
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see if this links to it....
Re: 12V wiring to hall light and bath [message #117157 is a reply to message #117156] Tue, 01 March 2011 21:25 Go to previous messageGo to next message
cjonesgo is currently offline  cjonesgo   United States
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oops. no link...

try this:
http://s197.photobucket.com/albums/aa272/cjonesgo_2007/GMC%20Motorhome/?action=view&current=12vWiringDiagram.jpg

Re: 12V wiring to hall light and bath [message #117163 is a reply to message #117156] Tue, 01 March 2011 22:13 Go to previous messageGo to next message
jtblank is currently offline  jtblank   United States
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Link works, the PO ran a new dedicated line to the fridge from an add-on 4 fuse DC block below the OEM 7 line. What's weird is the front right light should be on the bath line but it works as well as rear reading, but the bath is dead. By the way my floorplan is a 26-09.
Thanks again.


John Blankenship '76 Palm Beach Tulare, CA
Re: 12V wiring to hall light and bath [message #117174 is a reply to message #117135] Wed, 02 March 2011 00:11 Go to previous messageGo to next message
jtblank is currently offline  jtblank   United States
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Well now it gets even better, I shorted out the hall light at lunch today at work and driving home tonight in the dark I noticed when I was getting out that there was light in the bath leaking through the crack around the door. I opened the door and believe it or not the bath light was on.... I turned it off and then turned the other side on and it worked... then turned it off and now neither one works... What the sh*# is this thing haunted? I can only think that the driving moved something (connection) that is loose. It's late already but I'll let you what and when I find something. Anybody got any ideas where to start?

Thanks


John Blankenship '76 Palm Beach Tulare, CA
Re: 12V wiring to hall light and bath [message #117177 is a reply to message #117174] Wed, 02 March 2011 00:50 Go to previous messageGo to next message
cjonesgo is currently offline  cjonesgo   United States
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jtblank wrote on Tue, 01 March 2011 22:11

Anybody got any ideas where to start?

Thanks



Sounds like an exorcism would be a good place to start...


One thing I have noticed with my original lights is that the switches can best be described as temperamental. One of them in particular needs a good deal of coaxing to come on. Could it be as simple as a faulty switch? Symptoms do sounds similar to the way my twitchy light behaves.
Re: 12V wiring to hall light and bath [message #117180 is a reply to message #117157] Wed, 02 March 2011 03:42 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Nice Diagram!

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] 12V wiring to hall light and bath [message #117192 is a reply to message #117180] Wed, 02 March 2011 08:05 Go to previous messageGo to next message
comcast is currently offline  comcast   United States
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Excellent, just in time for my rewiring scheme.

Roger Black
77 Birchaven
Burns, Tn




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Re: [GMCnet] 12V wiring to hall light and bath [message #117216 is a reply to message #117157] Wed, 02 March 2011 09:44 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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It would be great if I could figure out
how to print it correctly!

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~



----------------------------------------
> To: gmclist@temp.gmcnet.org
> From: cjonesgo@yahoo.com
> Date: Tue, 1 Mar 2011 21:25:12 -0600
> Subject: Re: [GMCnet] 12V wiring to hall light and bath
>
>
>
> oops. no link...
>
> try this:
> http://s197.photobucket.com/albums/aa272/cjonesgo_2007/GMC%20Motorhome/?action=view¤t=12vWiringDiagram.jpg
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Re: [GMCnet] 12V wiring to hall light and bath [message #117232 is a reply to message #117216] Wed, 02 March 2011 13:13 Go to previous messageGo to next message
Bob Horton is currently offline  Bob Horton   Canada
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GMC wiring can be tricky.

Had a problem with my outside light. Checked the the bulb - it checked ok with an ohmmeter - still no light. Checked the socket - 12 volts at light ok. didn't seem to make sense. Changed the bulb - still no light. Checked the switch - ok to pass enough current for a digital meter - but not enough for the bulb. Changed the switch - then ok. Who's to guess.

I also changed the outside bulb to a LCD bulb so it can be left on overnight if desired.

Bob Horton
Brandon, Manitoba (miserably cold here)
Re: [GMCnet] 12V wiring to hall light and bath [message #117459 is a reply to message #117232] Fri, 04 March 2011 02:38 Go to previous messageGo to next message
cjonesgo is currently offline  cjonesgo   United States
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Because of this thread I decided to check the lights in my bath. I have been using it as a storage closet while I rebuild, and don't think that I have ever even tried to turn on the lights...

Sure enough, lights don't work!

I am getting full current to the light, but switches have failed. I had planned to replace them anyway, so not a big deal.
Re: [GMCnet] 12V wiring to hall light and bath [message #117463 is a reply to message #117459] Fri, 04 March 2011 04:09 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Some contact cleaner sprayed into the switches will often solve the
problem. It has a lubricant in it that prevents oxidation and
corrosion of the contacts.

Emery Stora


Emery

On Mar 4, 2011, at 1:38 AM, corey jones <cjonesgo@yahoo.com> wrote:

>
>
> Because of this thread I decided to check the lights in my bath. I
> have been using it as a storage closet while I rebuild, and don't
> think that I have ever even tried to turn on the lights...
>
> Sure enough, lights don't work!
>
> I am getting full current to the light, but switches have failed.
> I had planned to replace them anyway, so not a big deal.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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Re: [GMCnet] 12V wiring to hall light and bath [message #117515 is a reply to message #117232] Fri, 04 March 2011 11:35 Go to previous messageGo to next message
cjonesgo is currently offline  cjonesgo   United States
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One of my other lights has the "on for a second" behavior sometimes, and it is the switch that is failing. I can jiggle it and get it to stay on. I'll try to contact cleaner and see if it helps. Thanks!

[Updated on: Fri, 04 March 2011 11:36]

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Re: [GMCnet] 12V wiring to hall light and bath [message #117518 is a reply to message #117515] Fri, 04 March 2011 12:17 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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Somebody else had mentioned "contact cleaner."

The BEST is "Deoxit" from the Caig company.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~~ ~ D C "Mac" Macdonald ~ ~~
~ ~ Amateur Radio - K2GKK ~ ~
~ ~ USAF and FAA, Retired ~ ~
~ ~ ~ Oklahoma City, OK ~ ~ ~
~~ ~ ~ "The Money Pit" ~ ~ ~~
~ ~ ~ ex-Palm Beach, 76 ~ ~ ~
~ www.gmcmhphotos.com/okclb ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~




> To: gmclist@temp.gmcnet.org
> From: cjonesgo@yahoo.com
> Date: Fri, 4 Mar 2011 11:35:42 -0600
> Subject: Re: [GMCnet] 12V wiring to hall light and bath
>
>
>
> Because of this thread I decided to check the lights in my bath. I have been using it as a storage closet while I rebuild, and don't think that I had ever even tried to turn on the lights...
>
> Sure enough, lights don't work!
>
> After a quick check, I am getting full current to the fixture, but switches have failed. On both lights! I had planned to replace them anyway, so not a big deal, but shows that these things do go bad.
>
> One of my other lights has the "on for a second" behavior sometimes, and it is the switch that is failing. I can jiggle it and get it to stay on.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
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Re: [GMCnet] 12V wiring to hall light and bath [message #117580 is a reply to message #117518] Fri, 04 March 2011 20:07 Go to previous messageGo to next message
cjonesgo is currently offline  cjonesgo   United States
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Contacts cleaned and all lights are working!

Still have plans to replace them, but now strictly for aesthetic reasons.
Re: [GMCnet] 12V wiring to hall light and bath [message #117619 is a reply to message #117580] Sat, 05 March 2011 02:04 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Atta Boy! Something so simple to do but which really does wonders. I
carry a can of contact cleaner with me in the GMC. I used to buy a
little can at Radio Shack but now find that I can buy a large spray
can at Ace Hardware for less.

Emery Stora

On Mar 4, 2011, at 7:07 PM, corey jones <cjonesgo@yahoo.com> wrote:

>
>
> Contacts cleaned and all lights are working!
>
> Still have plans to replace them, but now strictly for aesthetic
> reasons.
> _______________________________________________
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Re: [GMCnet] 12V wiring to hall light and bath [message #117640 is a reply to message #117619] Sat, 05 March 2011 09:22 Go to previous messageGo to next message
rwbmitiopt@comcast.net is currently offline  rwbmitiopt@comcast.net   United States
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Emery
Are the switchs referred to the three position slide ones used on all the original lights? Mine are so bad I expect them to break rather than move.
Randall
emerystora wrote on Sat, 05 March 2011 00:04

Atta Boy! Something so simple to do but which really does wonders. I
carry a can of contact cleaner with me in the GMC. I used to buy a
little can at Radio Shack but now find that I can buy a large spray
can at Ace Hardware for less.

Emery Stora






Randall Burns
Sammamish WA
75 EX GB
Re: [GMCnet] 12V wiring to hall light and bath [message #117646 is a reply to message #117640] Sat, 05 March 2011 11:14 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Registered: January 2004
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Senior Member
Yes, those are the switches. They can get so stiff that they are hard
to move. The contact cleaner sprays have a lubricant that can do
wonders to free them up. Don't use WD40 as the oil will just attract
dust and gum them up even worse.

Emery Stora

On Mar 5, 2011, at 8:22 AM, rwbmitiopt <rwbmitiopt@comcast.net> wrote:

>
>
> Emery
> Are the switchs referred to the three position slide ones used on
> all the original lights? Mine are so bad I expect them to break
> rather than move.
> Randall
> emerystora wrote on Sat, 05 March 2011 00:04
>> Atta Boy! Something so simple to do but which really does
>> wonders. I
>> carry a can of contact cleaner with me in the GMC. I used to buy a
>> little can at Radio Shack but now find that I can buy a large spray
>> can at Ace Hardware for less.
>>
>> Emery Stora
>
>
> --
> Randall Burns
> Sammamish WA
> 75 EX GB
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Re: [GMCnet] 12V wiring to hall light and bath [message #118344 is a reply to message #117646] Thu, 10 March 2011 16:32 Go to previous messageGo to previous message
jtblank is currently offline  jtblank   United States
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Update....
I cleaned the switches and no go, tested the line in hallway and sometimes I get 12v sometimes not.. I just went out at lunch time and plugged the fixture back into the line and light went on.. hurray, I thought. Went into bath to check those lights and went on for a second and then off and the hall light went out too. Turned the bath light switch to off and unplugged hall fixture, played around hall line no +12v pulled the line in flex conduit abit and now +12v on line.. plugged back in no lights.. tested the wire lugs on back of switch 12v.

I'm no electrician (really a CPA) but my thoughts are were ever those two ground lines run (hall and bath) there must be a bad connection. I've cleaned the connection on the fuse panel for the + side but where do they ground? Also the fuse panel says that the hall light is on line 4 and bath is on 5 but they both are out and all the other items listed on the fuse guide work so obviously the power +12v is not the problem but rather the ground on the hall and light circuit? Maybe they are both grounded at same spot and when I arced the circuit taking down the hall fixture it oxidized the ground connection? Got enough +12v to measure but connection not good enough to power the 2amp bulbs?

I'm looking for some input here and where I should look next.
Thanks,


John Blankenship '76 Palm Beach Tulare, CA
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