car fuel sending unit

hello guys, am make a project to read a car fuel tank sending unit. my car is a toyota vits 2006. the sending unit has 2 wire attached to it.
at full tank i should get:33 ohm
empty:233 ohms.
my problem is i do not have to use an arduino to read the ohms values. am a new to electronic stuff. if anyone could brief me.

Are you trying to build something like a digital fuel gauge (or something like that), or do you just want to test the sender?

If you just need to check resistance (Ohms), a [u]multimeter[/u] can read resistance, voltage, and current (Amps).

You might be able to find a multimeter at an auto parts store, or a hardware store, but your best selection will be from some place that sells electronic parts.

Disconnect the sender from everything when measuring resistance. If there’s voltage applied or something else in the circuit, you’ll get an invalid reading.

thanks for the reply i want a digital fuel gauge. its for a project. dvddoug u think its possible to read it? :frowning:

As long as the car is not trying to read it at the same time.
Remember you can't go over 5V on an input.
I'm sure the car has 12V.
Usually the car puts a current meter inline with the 12V and then
one lead is grounded.
You can use your 5V pin and add a 100 ohm
Connect the one lead to ground of the sender and the
other to the 100 ohms other end.
Also run that junction to an analog input.
You'll most likely need to take measurements at different
amounts of fill of the tank.
Start with an empty tank and add one gallon at a time.
If it is linear, you can use map() to a display otherwise
you'll need to use a lookup table to convert the value.

thanks for the info dwightthinker, from what i understand i must disconnect both wire from sending unit. and power it with the arduino (5v). my problem is that i dont know how to connect the 100 ohms register.

The second post here has the sort of thing - use 100 instead of '1k typical'.