I'm trying to read a throttle position sensor with my Arduino Mega. This is the schematic for a normal TPS. It's a basic potentiometer.
However, this particular TPS only has 2 pins coming out. There's no ground, there's just the 5 volt reference and the signal return. I have one pin hooked up to the 5Volts on my Arduino and the other hooked up to an analog pin, which I am reading with analogRead. I'm getting strange readings at different positions. At position zero, it jumps around at around 300. As soon as I turn the sensor at all, it automatically jumps to 1023 and stays there.
What is the point of the ground in that diagram? What am I missing here, and how does that tie in to the odd TPS readings?