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Instrument gauge lights

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Old Apr 23, 2006 | 08:51 PM
  #1  
Yoruai's Avatar
Yoruai
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Default Instrument gauge lights

For some reason everything on my instrument panel works except the gauge lights. Gauges themselves - good, turn signals - good, break notification light - good, heater and wiper controls - good. The head lights work too so I dont' think it's the switch. I replaced all the bulbs and fuses to o avail. Even checked the gorund.
The only thing left was to undo the harness tape and see what went where. Below is a diagram of what I found. Only what I thought as relative to the problem is depicted. There are of course many other wires, most connected some not but everything other than the gauge lights are working.

I hope someone can help.

Blue/Orange = gauge lights
Yellow/Black = ???
Black = ???
All conecters are female

[IMG]local://upfiles/35135/CD225E6460044BEC8A435C8676DD61DE.jpg[/IMG]
Old Apr 23, 2006 | 09:37 PM
  #2  
Cogtx's Avatar
Cogtx
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From: Sugar Land, Texas
Default RE: Instrument gauge lights

Had the same prob awhile back. Headlight switch may need to be replaced OR just cleaned. Take the switch out and clean it with electrical cleaner and scrub connections with sandpaper. Be sure to clean the circular spring/wire (don't know the real name) on the front and the metal connector that touches that circular spring. Might have to slightly bend the connector so that it makes constant contact with the spring as you turn the ****. Once you get it out you will see what I'm taking about....good luck..

Old Apr 23, 2006 | 09:42 PM
  #3  
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fstrstang
 
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Default RE: Instrument gauge lights

That circular spring / wire, along with the contactor (arm), is a variable resistor, also known as a potentiometer. It is the part of the headlight switch that controls the brightness of the dash lights, and could be the cause of the problem.

John
Old Apr 23, 2006 | 09:47 PM
  #4  
Yoruai's Avatar
Yoruai
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Default RE: Instrument gauge lights

Great, I'll take a look. I wasn't sure if only part of the switch could go bad since it does still control the headlights. Any idea about thoes strange connectors down the line?
Old Apr 23, 2006 | 10:07 PM
  #5  
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tylerdru
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Default RE: Instrument gauge lights

My problem was the headlight switch and the ligths were not grounded properly.
Old Apr 23, 2006 | 10:28 PM
  #6  
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Yoruai
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Default RE: Instrument gauge lights

I see what you mean. Only had a little corrosion and bent the tab so that it rides the spring good but still no luck. Talk to me about the ground? Everything else works so I don't think thats the problem but who knows. The connecter that attaches the panel to the wireing harness has a wire that is screwed into the fram behind the dash. I beileve that is the ground. Does the headlight switch itself have to be grounded? It got a little hot when I was testing it.
Old Apr 23, 2006 | 10:49 PM
  #7  
Yoruai's Avatar
Yoruai
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Default RE: Instrument gauge lights

Ran a jumper stright to the panel lights and they worked. Aparently just the dimmer portion of the switch is bad. Thing looks brand new though. Thanks for the assistance. Couldn't have done it without ya.

Still would like to know what those wierd connecters are though. Additional gauges?
Old Apr 23, 2006 | 11:20 PM
  #8  
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Cogtx
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From: Sugar Land, Texas
Default RE: Instrument gauge lights

Kinda lost...what are the weird connectors you are referring to? Got pic?
Old Apr 24, 2006 | 06:49 PM
  #9  
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Yoruai
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Default RE: Instrument gauge lights

Replaced the switch with a brand new one and no change. Now what?

Pic of diagram are in first post.
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