Help! Electrical stuff. . .failing one by one. . .

[Bolisk]

While driving my car (1970 coupe) the other night, I noticed that my high beam fiber optics indicators did not show that the high beam bulbs were on. This was odd, because they were indicating that they were on a few minutes earlier. I cycled the high beam foot switch, and I noticed that the "BRIGHTS" indicator on the speedo would light and unlight as normal. . .but the high beam bulbs did not appear to be working, according to the fiber optics. I did notice that there was a "kinda" high beam effect when I hit the foot switch. . .but it wasn't as bright as it normally is. When I stoped for gas, I aske my wife to get out and check the lights, and she said that center two bulbs were not turning on. . .confirming the fiber optics.

Is there a fuse that would blow and cause this behavior?

Secondly, on the way into work early this am. . .I noticed that my dash board lights (back lights) stoped working, but turn signlas, brights, and parking break lights all still work.

Is there a fuse that would blow and cause this behavior as well?

These failures all seem selective. . .

Any help advice would be great.

-JR

 

[gmjunkie]

While driving my car (1970 coupe) the other night, I noticed that my high beam fiber optics indicators did not show that the high beam bulbs were on. This was odd, because they were indicating that they were on a few minutes earlier. I cycled the high beam foot switch, and I noticed that the "BRIGHTS" indicator on the speedo would light and unlight as normal. . .but the high beam bulbs did not appear to be working, according to the fiber optics. I did notice that there was a "kinda" high beam effect when I hit the foot switch. . .but it wasn't as bright as it normally is. When I stoped for gas, I aske my wife to get out and check the lights, and she said that center two bulbs were not turning on. . .confirming the fiber optics.

Is there a fuse that would blow and cause this behavior?

Secondly, on the way into work early this am. . .I noticed that my dash board lights (back lights) stoped working, but turn signlas, brights, and parking break lights all still work.

Is there a fuse that would blow and cause this behavior as well?

These failures all seem selective. . .

Any help advice would be great.

-JR

Inspect and Clean your grounds at the headlamp harness,You have a high resistance or non-existent ground in the front!~!!

 

[jims427400]

GM,I have the same issue with my 67 and 68. We're is the ground located?Thanks

 

[gmjunkie]

GM,I have the same issue with my 67 and 68. We're is the ground located?Thanks

Do you have any Idea how long it's been since I've had the nose apart on a Mid Year??? I think maybe 76,77,78,79,80,81,82your just going have to look for them up in the front on the core support,frame and headlamp assys,on the 68-82 c3's there will be one/maybe 2 wires(depending the year) I believe on the core support left front side and a couple on the underside of the metal headlamp mounting reinforcement bonded to the surround panel toward the middle!

PS the one/s on the core support may be hard to find because the hood may hide them when it's up!~!!

 

[Rod75]

While driving my car (1970 coupe) the other night, I noticed that my high beam fiber optics indicators did not show that the high beam bulbs were on. This was odd, because they were indicating that they were on a few minutes earlier. I cycled the high beam foot switch, and I noticed that the "BRIGHTS" indicator on the speedo would light and unlight as normal. . .but the high beam bulbs did not appear to be working, according to the fiber optics. I did notice that there was a "kinda" high beam effect when I hit the foot switch. . .but it wasn't as bright as it normally is. When I stoped for gas, I aske my wife to get out and check the lights, and she said that center two bulbs were not turning on. . .confirming the fiber optics.
Is there a fuse that would blow and cause this behavior?
Secondly, on the way into work early this am. . .I noticed that my dash board lights (back lights) stoped working, but turn signlas, brights, and parking break lights all still work.
Is there a fuse that would blow and cause this behavior as well?
These failures all seem selective. . .
Any help advice would be great. -JR

From your description on your bright lights, I would consider the foot switch. Bypass it to verify.
For your dash illumination lamps, check the fuse first.

 

[strokin383-c4]

Check your ground under your foot switch, oh and btw I dont believe fiber optics were invented till the 21'st century

 

[Rod75]

oh and btw I dont believe fiber optics were invented till the 21'st century

The Corvette Story: 1969 Corvette

http://www.zip-corvette.com/GroupDetails/GroupLanding1.aspx?gid={55660b24-aec5-487d-9b82-34d4c41d8735}&SearchType=_GROUP_SEARCH&GroupName=68-71%20Fiber%20Optics%20&%20Repair

 

[Bolisk]

The Corvette Story: 1969 Corvette

http://www.zip-corvette.com/GroupDetails/GroupLanding1.aspx?gid={55660b24-aec5-487d-9b82-34d4c41d8735}&SearchType=_GROUP_SEARCH&GroupName=68-71 Fiber Optics & Repair

I assumed stroken383 was being funny. Yeah. . .fiber optics have been arround a long time. The principals have been in place since the 1840's and ownes corning (i believe) had some major modern break throughs in the 1960 or 70's with glass that was clear enough to pass light over extreamly long distances.

 

[Rod75]

I assumed stroken383 was being funny. Yeah. . .fiber optics have been arround a long time. The principals have been in place since the 1840's and ownes corning (i believe) had some major modern break throughs in the 1960 or 70's with glass that was clear enough to pass light over extreamly long distances.

Exactly!

 

[TimAT]

I'll vote with GMjunkie- grounds. The core support is grounded to the rest of the frame/electrical system at the left front (if it close to my 69) and the forward lamp harness ground is on the front of the core support at the left front. There is nothing in the rules that says you can't run another ground wire too.