Using LED voltmeter as Fuel level
Printed From: the12volt.com
Forum Name: Lights, Neon, LEDs, HIDs
Forum Discription: Under Car Lighting, Strobe Lights, Fog Lights, Headlights, HIDs, DRL, Tail Lights, Brake Lights, Dashboard Lights, WigWag, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=46953
Printed Date: August 10, 2025 at 11:20 PM
Topic: Using LED voltmeter as Fuel level
Posted By: customcaraudio
Subject: Using LED voltmeter as Fuel level
Date Posted: January 05, 2005 at 6:44 AM
Just wondering if anyone out there is clued up on if you can use a voltmeter as a fuel gauge. Changing the LED's Around of course. But dont know if the oem fuel level is voltage driven or resistance to earth. If any one can give us a hand it would be appreciated. Or if anyone knows of any pcb kits around that would do the job. thanks
-------------
Daveo
Owner/Installer
Custom Car Audio
Australia
Replies:
Posted By: slammedb5
Date Posted: January 05, 2005 at 7:08 AM
I've used DMM's as air/fuel meters, but never as fuel gauges. Sorry.
Posted By: MrSector9
Date Posted: January 06, 2005 at 1:06 AM
Most Automobiles use resistance for the simple reason that voltage driven could posibly cause a spark and that would not be good,at least any I have ever seen used resistance not to say EVERYTHING does. I have used this method before to meausre the level in the tank when I couldn't get a gauge to work correctly.
BJ White
Posted By: customcaraudio
Date Posted: January 06, 2005 at 5:19 AM
I have hooked up a cheap led bar voltmeter with the fuel sender to one side and the positve to ignition. on a full tank of fuel his sender was saying -12.38 volts so we thought if it started to drop it would bring down the led lights. seem to work so far but we have to wait till the tank empties a bit. Another way we think might work would to use a series of resistors on 10 LEDs(2 red, 3 orange and 5 green), have them different resistances lower for red and higher for the top green and as the resistance on the fuel level dropped the resistance will be too high for the higher LEDs therefore they will turn off and act like a fuel gauge and start dropping to the red until the tank is empty. hope this is understandable.
-------------
Daveo
Owner/Installer
Custom Car Audio
Australia
|