NO gauge lights?
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
NO gauge lights?
Just popped the dash off.
Headlight vacuum side of switch works fine.
Electrical plug to switch I assume control gauge lights AND headlights once they pop up, right?
Headlights come on but gauge lights don't. Is this a common problem with these switches?
I checked my fuses too, they look fine.
Anyone?
Headlight vacuum side of switch works fine.
Electrical plug to switch I assume control gauge lights AND headlights once they pop up, right?
Headlights come on but gauge lights don't. Is this a common problem with these switches?
I checked my fuses too, they look fine.
Anyone?
Drifting
Joined: Jun 2005
Posts: 1,523
Likes: 1
From: grand prairie texas
Need more info. What year and did the lights just quit or have they been out for awhile. Looking at my 77 wiring diagram with your light switch to the on position you should have 12 volts to the 5 amp inst light fuse. Check if you are getting voltage down to the fuse first
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Design is the same, as wnmech says check the inst fuse for power when the switch is pulled out--check both sides of the fuse for power. might be a 4 amp though--- lower left in your fuse box
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
I have same problem, still can't figure it out. Tried new switch (autozone, non vacuum), no help. Have power at switch but no power at fuse. However, continuity test with my voltmeter indicates continuity between the switch and the fuse. I gave up on it for awhile but I need to get back to it - especially now that my rear tail lights aren't working but brake lights and turn signals do...
I will watch with interest, but won't get back to this until my DeWitts is in and fans are wired up.
Mine is a '74 btw, and i figured i didn't need the vacuum switch because i have stationary lights.
I will watch with interest, but won't get back to this until my DeWitts is in and fans are wired up.
Mine is a '74 btw, and i figured i didn't need the vacuum switch because i have stationary lights.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
On your continuity test. You can't do the cont test with everything hooked up. Remove the the connector at the switch and the inst light fuse. Put one probe on the green wire terminal and the other probe on the right fuse holder contact.
(I would rather see you use a 12v test light)
Burning Brakes
Joined: Apr 2007
Posts: 1,028
Likes: 1
From: SOUTH ELGIN IL
Your right good move.
On your continuity test. You can't do the cont test with everything hooked up. Remove the the connector at the switch and the inst light fuse. Put one probe on the green wire terminal and the other probe on the right fuse holder contact.
(I would rather see you use a 12v test light)
On your continuity test. You can't do the cont test with everything hooked up. Remove the the connector at the switch and the inst light fuse. Put one probe on the green wire terminal and the other probe on the right fuse holder contact.
(I would rather see you use a 12v test light)
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Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
You may have a grounding problem....or the rheostat in the light switch is shot. If you have 12vdc coming out of the switch, it just about has to be a grounding issue. Without a good ground, you really don't have 12 volt across the lights.
Drifting
Joined: Jun 2005
Posts: 1,523
Likes: 1
From: grand prairie texas
Ok it's good that you have 12 volts across the fuse. Next step in my opinion is you are probably going to have to disassemble the dash to first trace the wire from the fuse box to where it goes into the instrument clusters to see if you are getting voltage there. If I remember my tach/speedo cluster share the same ground and my gauges share a different ground but they could tie together in a common place. All the instrument lights should be grey and are grounded once they are plugged into the cluster.
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
I'm a little confused.
When I first bought the car the gauge lights worked when the headlight switch was pulled out. The dimmer didn't do anything except turn on the lights in the "locked out" position after rotating it.
Then one day they (gauge lights) just didn't come on anymore.
Seems like if the lights, both tach/speedo and gauge cluster, had good grounding points then those probably are still good. Although, maybe I do have that issue.
When I first bought the car the gauge lights worked when the headlight switch was pulled out. The dimmer didn't do anything except turn on the lights in the "locked out" position after rotating it.
Then one day they (gauge lights) just didn't come on anymore.
Seems like if the lights, both tach/speedo and gauge cluster, had good grounding points then those probably are still good. Although, maybe I do have that issue.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
I'm a little confused.
When I first bought the car the gauge lights worked when the headlight switch was pulled out. The dimmer didn't do anything except turn on the lights in the "locked out" position after rotating it.
Then one day they (gauge lights) just didn't come on anymore.
Seems like if the lights, both tach/speedo and gauge cluster, had good grounding points then those probably are still good. Although, maybe I do have that issue.
When I first bought the car the gauge lights worked when the headlight switch was pulled out. The dimmer didn't do anything except turn on the lights in the "locked out" position after rotating it.
Then one day they (gauge lights) just didn't come on anymore.
Seems like if the lights, both tach/speedo and gauge cluster, had good grounding points then those probably are still good. Although, maybe I do have that issue.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Did you check the term that the fuse pops into ? Sometimes if the fuse and the terminals are not making a good connection it will fool you. The power comes in the right side fuse contact and goes through the fuse into the left contact and then goes to the dash lights.
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
Wow thanks for all the great ideas everyone. I'll make sure to re-check those terminals and the fuse itself.
How does that saying go?
Electrical problems aren't hard to fix, just hard to find?
Something like that
How does that saying go?
Electrical problems aren't hard to fix, just hard to find?
Something like that
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
So you will all laugh at me, but I replaced the fuse that I thought was fine and the gauges light up now...but...
They only light up when the switch is rotated to the position that is just before "lockout" (lockout being the position that turns the rear compartment light on).
This now makes me think my switch rheostat has failed. So, I think I need a new switch.
Whaddaya think?
They only light up when the switch is rotated to the position that is just before "lockout" (lockout being the position that turns the rear compartment light on).
This now makes me think my switch rheostat has failed. So, I think I need a new switch.
Whaddaya think?
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
So you will all laugh at me, but I replaced the fuse that I thought was fine and the gauges light up now...but...
They only light up when the switch is rotated to the position that is just before "lockout" (lockout being the position that turns the rear compartment light on).
This now makes me think my switch rheostat has failed. So, I think I need a new switch.
Whaddaya think?
They only light up when the switch is rotated to the position that is just before "lockout" (lockout being the position that turns the rear compartment light on).
This now makes me think my switch rheostat has failed. So, I think I need a new switch.
Whaddaya think?
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
Sweet. I was pretty shocked when they came on, mainly because the switch wasn't rotated far enough and I figured I'd give it a spin. I'm glad I did.
Thanks for taking your time to help me everyone. You all are outstanding people, and you do a great service to pass along your knowledge whenever you find the time to.
Thanks for taking your time to help me everyone. You all are outstanding people, and you do a great service to pass along your knowledge whenever you find the time to.
