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new random electrical problem [message #103181] Sat, 16 October 2010 18:56 Go to next message
Neil is currently offline  Neil   United States
Messages: 271
Registered: July 2007
Location: Los Angeles and Magalia, ...
Karma: 1
Senior Member
I took the coach out for new front tires today and noticed a new electrical quirk.

The right turn signal - but only the right - made the in dash stereo/gps bink. I finally figured out the stereo/gps was getting a headlights on indication from where ever that was hooked up. (I did the instal but I forget where and how it is hooked up. More CRS.)

Then when I put the headlights on, the right turn indicator arrow illuminated on the dash.

So somewhere, the right turn signal is crossing over to the headlights (maybe just running lights?) circuit.

Any ideas where to dig in?

Thanks.


Neil
76 Eleganza now sold
Los Angeles
Re: new random electrical problem [message #103185 is a reply to message #103181] Sat, 16 October 2010 19:18 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
Sounds like ground loops and they are tough to chase down.
Start by making sure that you have good grounds on all 12v equipment. Remove the grounding cables, sand/file them smooth and shiny, coat with anti-oxidation coating, and reinstall the grounds. Make sure that the ground connection between the aluminum firewall and the engine still exists. I installed an additional ground strap from the aluminum firewall and the chassis for an additional ground path.
A faulty ground will cause problems that are difficult to trace, because the corrosion can act as a semi-conductor and disrupt/change the electrical values that the equipment needs to function properly. And, this value will change with age, vibration, and/or heat as they affect the joint.
You might also remove and reconnect any connectors that have been added to your electrical system. Especially, any connections made by the use of the "clip-on" type of wire clamps that seem to be added by P.O.'s. I do not trust these devices and have removed them from my coach as I encounter them.
Good Luck.

Tom Phipps,
75 GMC Ex-Avion


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] new random electrical problem [message #103202 is a reply to message #103181] Sat, 16 October 2010 20:57 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Double check your dash grounding. When I put the DIN stereo in my 78 Royale,
I also added some gages below the dash, and I have a vacuum gage and a Sun
tach between the drivers side windshield and the dash. I used the binding
post that used to be the rear hold down for the stock GM wonder bar radio
for a common grounding point. Also, don't hook any part of your radio to the
grey wire that seems to be hot, as it is wired through the headlight dimmer
and will do what you have described along with other wierd stuff. The grey
wire is to dim the dash lights. Double check that for sure.
Jim Hupy
Salem, Or
78 Royale 403

On Sat, Oct 16, 2010 at 4:56 PM, Neil Martin <nmartin@hfbllp.com> wrote:

>
>
> I took the coach out for new front tires today and noticed a new electrical
> quirk.
>
> The right turn signal - but only the right - made the in dash stereo/gps
> bink. I finally figured out the stereo/gps was getting a headlights on
> indication from where ever that was hooked up. (I did the instal but I
> forget where and how it is hooked up. More CRS.)
>
> Then when I put the headlights on, the right turn indicator arrow
> illuminated on the dash.
>
> So somewhere, the right turn signal is crossing over to the headlights
> (maybe just running lights?) circuit.
>
> Any ideas where to dig in?
>
> Thanks.
> --
> Neil
> 76 Eleganza
> Los Angeles
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: new random electrical problem [message #103206 is a reply to message #103181] Sat, 16 October 2010 21:33 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Neil wrote on Sat, 16 October 2010 16:56

I took the coach out for new front tires today and noticed a new electrical quirk.

The right turn signal - but only the right - made the in dash stereo/gps bink. I finally figured out the stereo/gps was getting a headlights on indication from where ever that was hooked up. (I did the instal but I forget where and how it is hooked up. More CRS.)

Then when I put the headlights on, the right turn indicator arrow illuminated on the dash.

So somewhere, the right turn signal is crossing over to the headlights (maybe just running lights?) circuit.

Any ideas where to dig in?

Thanks.


Neil,

It is undoubtedly a ground issue. It could also be something as simple as a bad parking light/turn signal bulb or a corroded socket that is causing said ground issue. Check the bulb on the right side and clean or replace it and see if the problem doesn't go away. If you have rodent problems, a wire might have been chewed off and be causing the problem also, by back-feeding from your running light to the other lights that are coming on.



Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] new random electrical problem [message #103218 is a reply to message #103206] Sun, 17 October 2010 00:43 Go to previous message
ljdavick is currently offline  ljdavick   United States
Messages: 3548
Registered: March 2007
Location: Fremont, CA
Karma: -3
Senior Member
Not exactly the same problem, but one of my turn signal lamps was out and it caused my right turn signal indicator to light when I turned on the headlamps. Looking at the bulb I couldn't tell that it was shorted but changing the bulb fixed the problem.

I stopped looking for the cause once the problem went away!

Larry Davick
The Mystery Machine
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
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