no lighting behind dash...help?
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Both of you before you go throught he hassle of changing the switch you should test to see if the switch in fact is not working.
To Test-put a test light on the "inst. light fuse"(check both sides of fuse to be safe)-pull headlight switch out-rotate **** both ways and watch the test light-If it lights up and dims and brightens as you rotate the **** then it is not bad.If it tests OK then you have a wiring problem not a headlight switch problem.
To Test-put a test light on the "inst. light fuse"(check both sides of fuse to be safe)-pull headlight switch out-rotate **** both ways and watch the test light-If it lights up and dims and brightens as you rotate the **** then it is not bad.If it tests OK then you have a wiring problem not a headlight switch problem.
Racer
Joined: Jun 2001
Posts: 460
Likes: 0
Another thing you can check is the windshield wiper switch................... I installed an '80 wiring harness in my "76 and ended up with no speedo & tach lights. After a week of analyzing the diagram I found out that GM in their infinite wisdom, ran the lighting wires for the speedo & tach thru the windshield wiper switch first, then to the dash ! I don't remember if these wires went to the center gauges or not, but definitely to the upper dash. If your not aware of this, it can be frustrating ! Good luck, Rick
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Its not too bad.Here are GMs instructions.Lighting switch,lower right hand corner
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
I have seen just the front part of the switch for sale but can't remember where. The entire switch is not expensive anyway.
Jim
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Depends on how big of a guy you are. I didn't have to do all that. Drop the lower dash pad....the peice that has the pulldown for the headlights on it. Lie on your back and reach up. Use a secrew driver to depress the button the holds the **** in the switch. While depressing pull the **** out. Remove the trim bezel on the outside. Drop the switch. disconnect the vaccum lines and electrical connections.
I have seen just the front part of the switch for sale but can't remember where. The entire switch is not expensive anyway.
Jim
I have seen just the front part of the switch for sale but can't remember where. The entire switch is not expensive anyway.
Jim
Note to C3 dont cross the 2 small hoses !!!
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Jim are you sure you didnt use the screwdriver to depress the speedo clip,because the button for the **** is on "top" of the switch?The button is the hardest part and like you said after the **** is out you can pull the switch down and then disconnect wiring and hoses.
Note to C3 dont cross the 2 small hoses !!!
Note to C3 dont cross the 2 small hoses !!!
Bubba had gotten to mine. The dimmer coil was broken and the previous owner wired the dash lights directly somehow bypassing the dimmer.
Jim
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Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I wonder if the switches are all the same. Mine you can get from the bottom. You can see the little button to the right of where the vac lines connect in the piture posted here. I have had it out several times. I followed the instructions in the book the first time. After the first time I did it the way I just posted.
Bubba had gotten to mine. The dimmer coil was broken and the previous owner wired the dash lights directly somehow bypassing the dimmer.
Jim
Bubba had gotten to mine. The dimmer coil was broken and the previous owner wired the dash lights directly somehow bypassing the dimmer.
Jim
Edit- Jim you are correct that darn button is on the bottom and very reachable with a screwdriver-I stand corrected.I should have remember being that I replaced one about a month ago.This getting old is tough.
Last edited by ...Roger...; Nov 12, 2007 at 12:59 PM.
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
The more I think about it you could be right,the button might be on the bottom.Heck I cant remember now.I know I have to stand on my head and wiggle my arm up inside there to push that dang button if I want to do it without removing the cluster.I usually try the way you posted first but I think the last time I gave up and went the long way.
Edit- Jim you are correct that darn button is on the bottom and very reachable with a screwdriver-I stand corrected.I should have remember being that I replaced one about a month ago.This getting old is tough.
Edit- Jim you are correct that darn button is on the bottom and very reachable with a screwdriver-I stand corrected.I should have remember being that I replaced one about a month ago.This getting old is tough.
Cheers,
Jim
Instructor
Joined: Oct 2007
Posts: 179
Likes: 0
From: Marvin North Carolina
1971-no dash/gauge lights
I was reading the posts here and have the same problem with my 71 vert I just bought this last week. This is my first vette, and have a lot to learn. On my car, you all are saying I should perform the test on the headlight switch in the dash first. As I understand it, I put my test light on the instrument light fuse? and then turn the **** back and forth? Did I get that right? If it is bad, I will get nothing or intermediate responses, depending upon where the "coil" is broken. Thanks in advance. 
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I was reading the posts here and have the same problem with my 71 vert I just bought this last week. This is my first vette, and have a lot to learn. On my car, you all are saying I should perform the test on the headlight switch in the dash first. As I understand it, I put my test light on the instrument light fuse? and then turn the **** back and forth? Did I get that right? If it is bad, I will get nothing or intermediate responses, depending upon where the "coil" is broken. Thanks in advance.
(Pull the **** out and turn headlights on during the test)
Instructor
Joined: Oct 2007
Posts: 179
Likes: 0
From: Marvin North Carolina
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Burning Brakes
Joined: Oct 2007
Posts: 946
Likes: 0
From: Lake Geneva WI
I have the exact same problem, though the 79" model year part does not appear to show a coil...
What I can tell you is, that my dimmer switch does have noticeable play in it, and wiggles. The interior lights do not work either, unless I wiggle the crap out of the switch and then lock it in the on position....
Seeing as how the dash lights and gauges do NOT work, I would be more inclined to think this IS a dimmer switch problem since the interior lights DO work if I wiggle the switch, but they only come on/off, they do not dim at all...
I would imagine that the dash lights are only on/off on the dim mode, not the toggle on mode.
Anyway, I think I will start there, ie., replace that part and see if that solves it. The bulbs all work and the fuses are fine, so what else could it be?
What I can tell you is, that my dimmer switch does have noticeable play in it, and wiggles. The interior lights do not work either, unless I wiggle the crap out of the switch and then lock it in the on position....
Seeing as how the dash lights and gauges do NOT work, I would be more inclined to think this IS a dimmer switch problem since the interior lights DO work if I wiggle the switch, but they only come on/off, they do not dim at all...
I would imagine that the dash lights are only on/off on the dim mode, not the toggle on mode.
Anyway, I think I will start there, ie., replace that part and see if that solves it. The bulbs all work and the fuses are fine, so what else could it be?
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
I have the exact same problem, though the 79" model year part does not appear to show a coil...
What I can tell you is, that my dimmer switch does have noticeable play in it, and wiggles. The interior lights do not work either, unless I wiggle the crap out of the switch and then lock it in the on position....
Seeing as how the dash lights and gauges do NOT work, I would be more inclined to think this IS a dimmer switch problem since the interior lights DO work if I wiggle the switch, but they only come on/off, they do not dim at all...
I would imagine that the dash lights are only on/off on the dim mode, not the toggle on mode.
Anyway, I think I will start there, ie., replace that part and see if that solves it. The bulbs all work and the fuses are fine, so what else could it be?
What I can tell you is, that my dimmer switch does have noticeable play in it, and wiggles. The interior lights do not work either, unless I wiggle the crap out of the switch and then lock it in the on position....
Seeing as how the dash lights and gauges do NOT work, I would be more inclined to think this IS a dimmer switch problem since the interior lights DO work if I wiggle the switch, but they only come on/off, they do not dim at all...
I would imagine that the dash lights are only on/off on the dim mode, not the toggle on mode.
Anyway, I think I will start there, ie., replace that part and see if that solves it. The bulbs all work and the fuses are fine, so what else could it be?
Jim
Burning Brakes
Joined: Oct 2007
Posts: 946
Likes: 0
From: Lake Geneva WI
The dimmer does work to left and right.. It dims only the speedo and tach. The interior lights come on when I turn all the way to the left. So the dimmer DOES work. Just the center gauges do not.