Fuel gauge wiring diagram

Tiny
BONESMIKE
  • MEMBER
  • 1982 OLDSMOBILE DELTA 88
  • 5.7L
  • V8
  • 2WD
  • AUTOMATIC
  • 19,900 MILES
Fuel gauge stopped working, fuel sending unit replaced. Gauge replaced still not working. It is a 3 stud gauge. Pulled out cluster did not have a meter so I checked with a test light. Looking at dash post on left was hot key on bottom was ground right post hole nothing. Was told left is gauge right is 12 volt bottom is ground. Any help?
Monday, January 11th, 2021 AT 4:21 PM

7 Replies

Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Hello, I'm Danny.

Here is the wiring diagram you requested. Here also is a tutorial showing how to test wiring:

https://www.2carpros.com/articles/how-to-check-wiring

I've attached the diagram below. Hope this helps and thanks for using 2CarPros.
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Monday, January 11th, 2021 AT 10:50 PM
Tiny
BONESMIKE
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  • 21 POSTS
Picture is hard to read kind of fuzzy.
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Tuesday, January 12th, 2021 AT 1:48 PM
Tiny
KASEKENNY
  • MECHANIC
  • 18,907 POSTS
I broke it into sections for you which should show up a little better. Thanks
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Friday, January 15th, 2021 AT 5:47 PM
Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Hello again.

Hope you were able to view the diagram with the larger pictures. Here is a tutorial on how to test electrical wiring:

https://www.2carpros.com/articles/how-to-check-wiring

Let us know what you were able to find out or if you have any further questions on this issue. Thanks again for using 2CarPros.

Danny-
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Saturday, January 23rd, 2021 AT 3:55 PM
Tiny
BONESMIKE
  • MEMBER
  • 21 POSTS
Does the ground wire on the tank sending unit if it comes loose or if there is not one can this cause a malfunction?
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Wednesday, February 24th, 2021 AT 11:39 PM
Tiny
KASEKENNY
  • MECHANIC
  • 18,907 POSTS
In short, yes this will cause an issue. Basically if there is no ground, it will either not respond or act erratically if it is able to find a ground through another part. This is called back feeding so clearly this ground shown below needs to be intact.

Thanks
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Thursday, February 25th, 2021 AT 6:23 PM
Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Hello again.

I agree that you definitely need to check all grounds. Let us know if the diagrams helped or if you have any further questions on this issue. Thanks again for using 2CarPros and keep us updated.

Danny-
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Saturday, February 27th, 2021 AT 6:08 PM

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