mishu 0 Posted March 29, 2007 Hello, can anyone tell me how to read the fuel sensor? I'm working on a project to replace the original instrument panel in a 1.1 205 with a LCD, controlled by a microcontroller. I'm at school right now, and don't have access to the car (to read the wires from the sensor with a multimeter). I have the instrument panel with me, but I don't know what to apply to the fuel gauge inputs. The back of the fuel gauge on the 1.1 has 3 inputs. From the wiring guide on the main site, and from other earlier testing I had done, I was able to work out what they are: Can anyone please confirm if these notations are correct, and what signal I have to connect to the 'Signal' input? Does the fuel gauge work like an ohm-meter, measuring electrical resistance in the sensor? Or does it read an electrical signal, like a voltmeter? I really need to confirm this so I can proceed Thanks! mishu Share this post Link to post Share on other sites
Richie-Van-GTi 71 2 Cars Posted March 30, 2007 the sender is a kind of potentiometer where tyhe float arm rubs against the contact strip to give varying resistance Share this post Link to post Share on other sites
mishu 0 Posted March 30, 2007 So I'd need to use an ohmmeter to measure electrical resistance between the signal input and ground? mishu Share this post Link to post Share on other sites
Super Josh 4 Posted March 30, 2007 Well, you could either measure the resistance with an Ohmeter or, better still, you could apply a voltage across it, say a regulated 5V (if you use the battery voltage this is not stable enough and your readings will vary depending upon whether the engine is running etc.). Then just measure the variable voltage coming back on the signal line If you use a Microcontroller with an inbuilt Analogue to Digital converter, then the only external circuitry you will need is the regulated 5V. Josh Share this post Link to post Share on other sites
mishu 0 Posted March 30, 2007 Yes, I am planning to use a microcontroller with an integrated ADC. Where should I apply the 5V? I don't know where the fuel sensor inputs are located, I assume that's what I should connect the board to? I was hoping to solve this from the instrument panel loom alone... Also, isn't there a fire hazard associated with applying a voltage to the inside of a gas tank? Share this post Link to post Share on other sites
