i want to install a level sensor in the water tank. i would like an LED to light when the levels falls below 1/4 or so.

what is the least expensive, reliable way to to this?

justin

 

If you found a car that had a windshield washer level detector in it stock you might be able to go to a junk yard and pull it from the same model. Just an idea if you are looking for something cheap.
Evan

 

use the stock FD water level sensor, it grounds out when water is present

 

Only if the water container is metal.

 

damn, really?

 

Yeah, the sensor works in the FD because the thermostat housing is metal and grounded. Since it's a single-wire sensor it needs the housing (and water) to act as a second electrode to complete the circuit.

You can still use the FD sensor with a non-metallic container if you add another electrode (or a second water sensor) to the container, but this is probably more trouble than it's worth, since there are off-the-shelf sensors that are made for this type of thing.