80 Low fuel light
Thread Starter
Intermediate
Joined: Jul 2005
Posts: 38
Likes: 0
80 Low fuel light
I am trying to get the low fuel light in my 80 working again. I pulled out the small circuit board from behind the low fuel indicator and had a electronics tech troubleshoot it. He found a bad transistor and a bad capacitor which he replaced and is pretty sure the circuit board is now OK. I reinstalled the board but light never came on even though fuel indicated well below the red warning line at E.
Is there any way to test or check if the the correct signal is being sent to the Low fuel circuit board from the gas gauge?
Is there any way to test or check if the the correct signal is being sent to the Low fuel circuit board from the gas gauge?
Safety Car
Joined: Mar 2005
Posts: 3,503
Likes: 2
From: Raleigh NC
Yes. Measure the resistance from the fuel level sending unit when the tank low on fuel. Now get a resistor matching that amount and a few lower and put them across the leads to the fuel gauge. What you are doing is sending and artifcial signal to the fuel gauge to see when the fuel light comes on.
Melting Slicks
Joined: Jul 1999
Posts: 3,030
Likes: 17
From: White Pine / Dandridge TN
Did you check the printed circuit board for continuity all the way to the low fuel light. Also, did you check the bulb itself...silly question but you never know. I had some bulbs that did not work due to the metal contacts on the bulb socket. I used a pencil eraser to clean the contacts.
Thread Starter
Intermediate
Joined: Jul 2005
Posts: 38
Likes: 0
Thanks guys,
I will try measuring the resistance. Where is the best place to take this reading?
I checked for voltage to ground at the signal terminal behind the gas gauge and got no voltage only continuity. Is that how it should be?
I will try measuring the resistance. Where is the best place to take this reading?
I checked for voltage to ground at the signal terminal behind the gas gauge and got no voltage only continuity. Is that how it should be?
Safety Car
Joined: Mar 2005
Posts: 3,503
Likes: 2
From: Raleigh NC
If you get under the car and look up near the drivers side muffler, you'll see some wires above it. One pair will be connected together with a black rubber connector that is shaped kinda like a link breakfast sausage. Pull this apart and take a resistance reading here.
Here's a post I did earlier on how to calibrate your fuel level reading:
http://forums.corvetteforum.com/show...tor&forum_id=3
Here's a post I did earlier on how to calibrate your fuel level reading:
http://forums.corvetteforum.com/show...tor&forum_id=3
Last edited by PhotoVette1; Oct 22, 2005 at 05:35 AM.
