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1966 Engine/Firewall grounding issue

  • Thread starter Thread starter Veneratio
  • Start date Start date May 23, 2021
V

Veneratio

Member
May 23, 2021
5
2
13
Michigan
May 23, 2021
#1
  • May 23, 2021
  • #1
Hi, I am sure some of you have expereinced this issue and I hope you can shed some light on it for me. For the past five years I have been restoring a 1966 Mustand 2dr couple. I am down to the fine details now and almost ready to be finished, well as finished as one can be with a vintage car - you know what I mean.
I am having an issue getting the courtesty lights to come on. I replaced all the bulbs, door switches, checked the interior grounds and voltage checked the fuse block. All are good.
For some reason these lights will not turn on.
I turned the headlight swtich all the way to the left, nothing. Activating the door switches, nothing. Checked the bulbs and sockets - they all work. I was reading a thread that mentioned a grounding strap from the right side of the engine to the firewall. I can not locate a grounding strap. There is a "vacant" hole in the firewall, where it appears one should be mounted, but nothing there.
My question is: What other electrical components are affected by this apparently missing grounding strap? What else can I check? Does this grounding strap only affect the "internal" lighting (glovebox, underdash courtesy lights, console lights etc.?
The engine starts and runs great, radio works, headlights, turn signals, brake lights - all are working.
Thanks everyone - I will post a picture once I get everything completed.
 
D

dmck

New Member
Jan 3, 2020
7
0
1
Adelaide, Australia
May 28, 2021
#2
  • May 28, 2021
  • #2
The strap between engine and car body is usually to assist the operation of the starter. It is rare for the battery negative terminal to be connected to the engine b- it usually connects to the body somewhere near the battery- hence the strap from body to block.
Are your courtesy lights and switches genuine parts or 'after-market' add ons? -- it may be they dont operate the way you think they do.

Its very difficult to give advice without actually inspecting the car/problem. As I'm on the other side of the world... that's not going to happen.... so...
Have you changed the wiring loom? ie is it standard wiring? If I down-load a '66 wiring diagram- will it be accurate for your car?

In the meantime-- someone else will no doubt offer their thoughts too....
 
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