C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

C3 Chassis Grounds

Thread Tools
 
Search this Thread
 
Old Jun 10, 2018 | 11:26 AM
  #1  
MBrianB's Avatar
MBrianB
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2014
Posts: 705
Likes: 96
From: Ventura County CA
Default C3 Chassis Grounds

Is there a source for a list of the chassis grounds on a C3? For my C5 there is a guide and picture of all the grounds in the AIM.

I'm having weird problems with grounds.
Reply
Old Jun 10, 2018 | 03:06 PM
  #2  
Street Rat's Avatar
Street Rat
Le Mans Master
Supporting Lifetime
15 Year Member
Conversation Starter
Community Favorite
 
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
Default

Originally Posted by MBrianB
Is there a source for a list of the chassis grounds on a C3? For my C5 there is a guide and picture of all the grounds in the AIM.

I'm having weird problems with grounds.

There isn't a "list" of grounds in the AIM. There are however detailed images showing the grounds for each system.


Craig
Reply
Old Jun 10, 2018 | 03:15 PM
  #3  
MBrianB's Avatar
MBrianB
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2014
Posts: 705
Likes: 96
From: Ventura County CA
Default

I can’t find them anywhere.
Reply
Old Jun 10, 2018 | 03:24 PM
  #4  
henrikse's Avatar
henrikse
Pro
 
Joined: Nov 2016
Posts: 729
Likes: 118
From: Kelowna British Columbia
Default grounds

Originally Posted by MBrianB
Is there a source for a list of the chassis grounds on a C3? For my C5 there is a guide and picture of all the grounds in the AIM.

I'm having weird problems with grounds.
I'll chime in with the ones I know
Beside starter at frame. Also from here there is a #6 cable to engine ground.
Below battery box at frame Negative from battery goes here.
Just below fuse box on birdcage does most of dash.
Ground goes thru center bezel and at top of bezel to metal under dash
On frame by rear taillights at frame.

There are probably more that others know but for a start find these and take apart and clean with emery cloth or wire brush and put back together.
Maybe mention where you are having weird problems
Reply
Old Jun 10, 2018 | 03:28 PM
  #5  
MBrianB's Avatar
MBrianB
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2014
Posts: 705
Likes: 96
From: Ventura County CA
Default

Originally Posted by henrikse
I'll chime in with the ones I know
Beside starter at frame. Also from here there is a #6 cable to engine ground.
Below battery box at frame Negative from battery goes here.
Just below fuse box on birdcage does most of dash.
Ground goes thru center bezel and at top of bezel to metal under dash
On frame by rear taillights at frame.

There are probably more that others know but for a start find these and take apart and clean with emery cloth or wire brush and put back together.
Maybe mention where you are having weird problems
What I do not understand is when I connect my test light to the horn relay hot point I get 12V at the radiator surround (grounded) and at the HL ground (grounded).

Those two ground points have continuity to each other and each to the battery neg. Headlights only go on when I connect another ground to the radiator surround. I just don't get it.
Reply
Old Jun 10, 2018 | 03:34 PM
  #6  
Street Rat's Avatar
Street Rat
Le Mans Master
Supporting Lifetime
15 Year Member
Conversation Starter
Community Favorite
 
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
Default

What year car are you working on MBrianB?

I'll get some photos if I can help.
Reply
Old Jun 10, 2018 | 03:37 PM
  #7  
MBrianB's Avatar
MBrianB
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2014
Posts: 705
Likes: 96
From: Ventura County CA
Default

Originally Posted by Street Rat
What year car are you working on MBrianB?

I'll get some photos if I can help.
'72 looking at my AIM now. What page (s)?
Reply
Old Jun 10, 2018 | 03:51 PM
  #8  
theandies's Avatar
theandies
Team Owner
20 Year Member
Veteran: Air Force
Community Favorite
Top Answer: 1
 
Joined: Jun 2001
Posts: 23,375
Likes: 1,066
From: Virginia USA
Default

Originally Posted by MBrianB
'72 looking at my AIM now. What page (s)?
Look at my "stitch the AIM wiring diagram together" thread. It will show you all the grounds.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old Jun 10, 2018 | 11:38 PM
  #9  
henrikse's Avatar
henrikse
Pro
 
Joined: Nov 2016
Posts: 729
Likes: 118
From: Kelowna British Columbia
Default

Originally Posted by MBrianB
What I do not understand is when I connect my test light to the horn relay hot point I get 12V at the radiator surround (grounded) and at the HL ground (grounded).

Those two ground points have continuity to each other and each to the battery neg. Headlights only go on when I connect another ground to the radiator surround. I just don't get it.
Reading a ground with a test light bulb's very low current. Lighting the headlights is way higher current so you are reading a ground thru something just not a good ground
Reply
Old Jun 10, 2018 | 11:41 PM
  #10  
MBrianB's Avatar
MBrianB
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2014
Posts: 705
Likes: 96
From: Ventura County CA
Default

Originally Posted by henrikse
Reading a ground with a test light bulb's very low current. Lighting the headlights is way higher current so you are reading a ground thru something just not a good ground
My frame and all the attached parts have been powder coated. None of the metal to metal connections are happening.

I had to find a good ground on the frame and run a separate ground to that point from the radiator surround. Lights work now.
Reply
Old Jun 11, 2018 | 09:46 AM
  #11  
69Vett's Avatar
69Vett
Safety Car
15 Year Member
 
Joined: Oct 2007
Posts: 3,729
Likes: 267
From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
Default

remove powder coating for all Gnd. connections grind down to bare metal.
Reply
Old Jun 11, 2018 | 04:42 PM
  #12  
One Owner's Avatar
One Owner
Lifelong Vette Lover
Supporting Lifetime
10 Year Member
Liked
Loved
 
Joined: Feb 2016
Posts: 177
Likes: 35
From: Naples FL
Default

I also replaced the two ground straps from the center crossmember to the exhaust hangers. That made a big difference though I'm still trying to cure a slight problem when the headlights are on. Good luck!
Reply
Old Jun 11, 2018 | 05:12 PM
  #13  
theandies's Avatar
theandies
Team Owner
20 Year Member
Veteran: Air Force
Community Favorite
Top Answer: 1
 
Joined: Jun 2001
Posts: 23,375
Likes: 1,066
From: Virginia USA
Default

This is what I used to clean up my grounding points. Couple of quick hits with one of these will clean any rust or paint (and powder coating) to make a good connection. When I first got the car I went through all the grounds that are easy to get to and replaced all the round eyelet connectors with new ones and soldered them on top of crimping them and cleaned the frame surface with the wire brush.

Reply

Get notified of new replies

To C3 Chassis Grounds





All times are GMT -4. The time now is 12:28 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE