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Electrical problem. Need help [message #320508] Sat, 15 July 2017 19:52 Go to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Senior Member
Helping my friend. 1977 eleganza ii. All systems seemed to work well, then it just died.

But then came alive.

Batteries are good.

Here is info:
Head lights don't work. Looks like another new switch. There is something differently wrong. If the dash lights don't come on, there is no power to start it. If the dash lights work, than I can start it. But I made it up here. It's cold and windy. Jeff says 👋

Headlight switch is new. Any idea how power gets to starter/ect??? That would be related??

Checking basics,
But all should be ok. Pushing boost did not work. Should have good battery connections.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] Electrical problem. Need help [message #320511 is a reply to message #320508] Sat, 15 July 2017 20:11 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Jon,

If you don't have the chassis wiring diagram, you should download it from
bdub.net.

Looking at that diagram, you'll see that there are numerous possible
locations for the sort of intermittent failure you're experiencing, but the
most likely is the Fusible Link, through which all chassis power except the
primary starter current must pass. It's easy to find that -- in the left
margin of the diagram there's a label at the level of the actual diagram.

Since that little 16 gauge wire carries a LOT of current all the time the
coach is in operation, it, and its connectors do deteriorate over time and
can be come intermittent. You should be able to buy replacement wire at
'most any auto parts store. DON'T just replace it with ordinary wire -- it
may run too hot for ordinary insulation.

Ken H.


On Sat, Jul 15, 2017 at 8:52 PM, Jon Roche wrote:

> Helping my friend. 1977 eleganza ii. All systems seemed to work well,
> then it just died.
>
> But then came alive.
>
> Batteries are good.
>
> Here is info:
> Head lights don't work. Looks like another new switch. There is something
> differently wrong. If the dash lights don't come on, there is no power to
> start it. If the dash lights work, than I can start it. But I made it up
> here. It's cold and windy. Jeff says 👋
>
> Headlight switch is new. Any idea how power gets to starter/ect??? That
> would be related??
>
> Checking basics,
> But all should be ok. Pushing boost did not work. Should have good
> battery connections.
> --
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Electrical problem. Need help [message #320512 is a reply to message #320508] Sat, 15 July 2017 20:25 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Registered: November 2013
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Senior Member
Check the main connections at the battery post, starter, and ground wire on the engine block. Starter power comes right from the battery, but the signal wire to trigger it may be fed from the connection at the starter, like most early GM cars. In forty years some owners may have made modifications to that setup, so YMMV.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: Electrical problem. Need help [message #320513 is a reply to message #320508] Sat, 15 July 2017 20:28 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
Thanks Ken.

I was looking over the diagrams on my phone and I came to that same fusable link as a probable culprit. You are confirming that educated guess.

The coach is a friend of mine I helped buy the coach. I am on my family camp trip and he headed north to thunder bay canada this weekend. So trying to help fix over phone. Electrical stuff is one thing that he struggles with.



Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Electrical problem. Need help [message #320514 is a reply to message #320508] Sat, 15 July 2017 20:31 Go to previous messageGo to next message
SeanKidd is currently offline  SeanKidd   United States
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Location: Northern Neck Virginia
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Senior Member
+1 for the main battery connections, they may look tight and be tight, but a layer of corrosion will insulate posts...remove, clean, reinstall, spray with battery terminal protector...also check chassis side of ground...

Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
Re: Electrical problem. Need help [message #320515 is a reply to message #320508] Sat, 15 July 2017 20:37 Go to previous messageGo to next message
wally is currently offline  wally   United States
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Registered: August 2004
Location: Omaha Nebraska
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Senior Member
lqqkatjon wrote on Sat, 15 July 2017 19:52
Helping my friend. 1977 eleganza ii. All systems seemed to work well, then it just died.

But then came alive.

Batteries are good.

Here is info:
Head lights don't work. Looks like another new switch. There is something differently wrong. If the dash lights don't come on, there is no power to start it. If the dash lights work, than I can start it. But I made it up here. It's cold and windy. Jeff says 👋

Headlight switch is new. Any idea how power gets to starter/ect??? That would be related??

Checking basics,
But all should be ok. Pushing boost did not work. Should have good battery connections.

Here is picture of the fusable link, not my pic.
http://www.gmcmhphotos.com/photos/misc-gmc-photos/p36632-fusable-link.html
http://www.gmcmhphotos.com/photos/misc-gmc-photos/p36632-fusable-link.html


Wally Anderson
Omaha NE
75 Glenbrook
Re: Electrical problem. Need help [message #320517 is a reply to message #320508] Sat, 15 July 2017 20:51 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
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Senior Member
Clean the battery cables thoroughly. Sometimes a round battery cable brush is not good enough. I have had to take a rat tail file to the battery cables to get them clean enough to really make good high current contact.

The fusible link that Colonel Ken mentioned is right in front of you when you open the passenger side hood. Move it around and flex it a bit to see if it is burned. A better way is to check all connections including the fusible link is with a volt meter under load.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Updated on: Sun, 16 July 2017 01:55]

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Re: Electrical problem. Need help [message #320537 is a reply to message #320508] Sun, 16 July 2017 11:47 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Last communication they are not thinking it is that fusable link. Everything seems working, except headlights now. They looked over that wire closely. I am told high beams work, so maybe the floor switch.

But I still wonder about the fusable link and such, and i will be checking everything once it is back in my driveway next week. Something was loose or changed causing no power. ow beams could of died too, even though they are new headlights installed this spring.

Asked them to check grounds and battery cables, but I did replace all battery cables, and such last fall. They should be in good shape.



Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/

[Updated on: Sun, 16 July 2017 11:48]

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Re: Electrical problem. Need help [message #320540 is a reply to message #320537] Sun, 16 July 2017 12:01 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Registered: November 2013
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Senior Member
Check the bulkhead/firewall connection...should have mentioned that in my earlier post Confused

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: Electrical problem. Need help [message #320541 is a reply to message #320540] Sun, 16 July 2017 12:02 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Registered: November 2013
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That is, the one behind the fusebox.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Electrical problem. Need help [message #320543 is a reply to message #320537] Sun, 16 July 2017 11:59 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Registered: May 2010
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Senior Member
Check the wire harness connector on or near the dimmer switch, and the
dimmer switch itself. I have encountered similar issues as you describe,
and found problems there.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Jul 16, 2017 9:53 AM, "Jon Roche" wrote:

> Last communication they are not thinking it is that fusable link.
> Everything seems working, except headlights now. I am told high beams
> work, so
> maybe the floor switch.
>
> But I still wonder about the fusable link and such, and i will be
> checking everything once it is back in my driveway next week. Something
> was loose
> or changed causing no power. Headlights could of died too, even though
> they are new this spring.
>
> Asked them to check grounds and battery cables, but I did replace all
> battery cables, and such last fall. They should be in good shape.
>
>
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: Electrical problem. Need help [message #320584 is a reply to message #320508] Mon, 17 July 2017 10:15 Go to previous messageGo to next message
dshafer is currently offline  dshafer   United States
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Registered: June 2016
Location: SW Ohio
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Member
Fusible link is designed to be a one time failure protection device. I've never seen intermittent... though I have not seen that many. Often when they blow it is not obvious to see. The insulation holds together but is very flexible where the melting occurred. If you stretch the fusible link you'll see the insulation at the fault point get thin. very much like a rubber band.

1977 26 foot 403

[Updated on: Mon, 17 July 2017 10:17]

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Re: Electrical problem. Need help [message #320791 is a reply to message #320508] Fri, 21 July 2017 13:58 Go to previous message
lqqkatjon is currently offline  lqqkatjon   United States
Messages: 2324
Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
Quick update:

Coach made it up north of Thunder Bay, and back home to my driveway in central MN, only repeating the dead ignition 3 times. They also realized that they had no high beam headlights.


Diagnosis now was the wiring mess the PO did feeding off the fuse block, and just had bad connections. The high beams and the ignition problem were two separate issues. Looks like the high beams and the low beams feed 12v off of different spots of the fuse panel, and one was not making contact.

Anyway- I replaced the perfectly good fusable link with a new one(auto parts store sells that with correct ring terminals), and I traced out the problems.

the connectors and wiring harness off the fuse panel needs to be replaced, and i just happen to know where one is sitting 80 miles away, so I should have that in the next couple weeks. In the mean time, I know where to look for the problem, and I rigged it a little better, so it should work for a while.

Thanks for all the help.





Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
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