# Fuel gauge circuit

Discussion in 'The Projects Forum' started by gitbox, Apr 28, 2009.

1. ### gitbox Thread Starter New Member

Apr 27, 2009
2
0
I have a fuel sender that is not compatible with the fuel gauge. I'm sure there is some circuit that can be created to do the proper conversion.

Here is some data that should help the design engineers on this forum:

Fuel sender Meter current Gauge reading
=========== ============= =============
235 ohms 35mA Empty
35 ohms 75mA Full

Available supply: 13.8v

Schematic of the stock fuel gauge circuit:
+12.6v-----meter-----fuel gauge-----ground.

From my meter readings, it appears to be a linear relationship.

I have a good supply of electronics parts and enough experience to build whatever circuit is offered. (barring multi-layer PC boards and SMT components - I only do "hobbyist" circuits).

Thanks so much for your help.

2. ### thingmaker3 Retired Moderator

May 16, 2005
5,072
8
I'm no engineer, but try a 127 Ohm resistor in series. It will get you pretty close.

$\stackrel{12.6V}{127+235}$=34.8mA

$\stackrel{12.6V}{127+35}$=78mA