Interior/gauge light issue
Thread Starter
Instructor
Joined: May 2011
Posts: 159
Likes: 0
From: Charleston South Carolina
Interior/gauge light issue
Hello all,
Was looking for some advice on where to start on my 74 with my loss of lighting inside the vette - all the gauge lights are out and it does not appear that any fuses are blown... the door lights come on however once a door is open...
Thanks!
Was looking for some advice on where to start on my 74 with my loss of lighting inside the vette - all the gauge lights are out and it does not appear that any fuses are blown... the door lights come on however once a door is open...
Thanks!
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Broken or disconnected grounding wire(s). There is one for the center gauge cluster that runs to metal framework around the cigarette lighter area; the speedo/tach ground wire runs from backside of speedo housing to the left side [front] door jamb frame.
Do you have lighting in the transmission tunnel area?
If you have no lighting inside the car (except for door/interior lights), see if the headlamp switch **** is rotated to the "low" or "off" position. The instument lights all work off that switch (for 12vdc power) and the rotation of that **** dims/brightens them. If you turn it full CW and still no lights, either the IP light fuse is bad or the dimmer part of the headlight switch is defective.
Do you have lighting in the transmission tunnel area?
If you have no lighting inside the car (except for door/interior lights), see if the headlamp switch **** is rotated to the "low" or "off" position. The instument lights all work off that switch (for 12vdc power) and the rotation of that **** dims/brightens them. If you turn it full CW and still no lights, either the IP light fuse is bad or the dimmer part of the headlight switch is defective.
Thread Starter
Instructor
Joined: May 2011
Posts: 159
Likes: 0
From: Charleston South Carolina
Thanks a lot for the advice - I think it's a ground issue near the kick panel on the drivers side... I thought the door lights were out as well till I bumped a wire by accident which in turn triggered the door lights on... I guess I will have to investigate that further...
As for the headlight switch, it is pretty loose - maybe it's no good anymore... how difficult are they to replace? I struggled removing that panel when I was in the process of restoring the interior...
As for the headlight switch, it is pretty loose - maybe it's no good anymore... how difficult are they to replace? I struggled removing that panel when I was in the process of restoring the interior...
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
It's a PITA, but it can be done.
#1 Pull the battery cable off before you start!
You really need a copy of the Assembly Instruction Manual (AIM) for your year car. It has all the detail of how 'stuff' goes together [or comes apart].
Basically, drop steering column a bit (don't need to remove it); remove attachments for the upper dash pad; pull pad off the retaining clips and lift it as much as possible without overstressing it; reach in between upper pad and top of driver's dash pad to 'do the deed'. The AIM will make sense on all of that.
#1 Pull the battery cable off before you start!
You really need a copy of the Assembly Instruction Manual (AIM) for your year car. It has all the detail of how 'stuff' goes together [or comes apart].
Basically, drop steering column a bit (don't need to remove it); remove attachments for the upper dash pad; pull pad off the retaining clips and lift it as much as possible without overstressing it; reach in between upper pad and top of driver's dash pad to 'do the deed'. The AIM will make sense on all of that.
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
I have replaced the light switch in my '79 but I've never had the dash pad out. I can't remember the details, but you may need to remove the instrument cluster, which might be easier than removing the dash pad. I would also be concerned about damaging a 30 year old dash pad by trying to lift one side of it. Have a good look at it befor etaking it apart to see what makes the most sense to you.
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,482
From: Southbound
Cruise-In II Veteran
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Joined: Aug 2006
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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Dash Gauge Lights
Tail light fuse feeds the headlight rheostat.
Jumper from "Courtest Light Fuse" to "Instrument Light Fuse"
if dash bulbs light up the rheostst in the headlight switch is bad.
Center gauge cluster and wiper switch ground through center terminal of
water temp gauge (14 gauge black wire).
The other end of that ground wire attaches to the left birdcage just above the left dash.
Schematic if you need it...
http://www.nrjvette.com/johdotukset/...tte%201974.pdf
Jumper from "Courtest Light Fuse" to "Instrument Light Fuse"
if dash bulbs light up the rheostst in the headlight switch is bad.
Center gauge cluster and wiper switch ground through center terminal of
water temp gauge (14 gauge black wire).
The other end of that ground wire attaches to the left birdcage just above the left dash.
Schematic if you need it...
http://www.nrjvette.com/johdotukset/...tte%201974.pdf
Thread Starter
Instructor
Joined: May 2011
Posts: 159
Likes: 0
From: Charleston South Carolina
Much appreciated - the diagrams and advice are very helpful - hopefully I will get to the bottom of it today... so nice out though, may end up driving it around instead!
Thanks so much!
Thanks so much!
