Re: Fuel Tank Surprise

Posted by HH56 On 2008/4/11 21:28:41

Temp gauge works same way, as does oil pressure on senior cars. They all work off approx 5v from a voltage regulator in a little square can behind instrument cluster that has a small heating element and bimetal strip inside. That opens and closes a set of contacts to change the 12 V to pulses which average out to 5v. Everything then gets grounded at respective sensors to complete the circuit.

As to using your sender, I would not recommend if it is truly 0 ohms because the gauge will be permanently damaged if allowed to sit at maximum. Install a 10 ohm resistor in the line so it won't hit maximum. Radio Shack has them--less than $2. Unfortunately, I don't know how much current flows to calculate the wattage but am guessing the 1 watt would be fine. If not, am sure someone on the forum will correct me. You'll have to see where that drives the needle and there probably won't be much range with that sensor.