Resistance spread on TPS?

[65ShelbyClone]

I'm talking about the resistance of a TPS with no power, not the voltage spread. I mostly just need to know which direction it ramps; does the resistance increase and the throttle opens, or does it decrease with more throttle? I figure that since the idle voltage is set at .95v and the ECU getting a 0-5v signal, the voltage can only go up from that initial .95v. In order to do that, the resistance has to go down in the TPS. Do I have this right?

 

[jrichker]

The TPS is a voltage divider network: one leg is wired to Signal Ground and the other to VREF power. The slider (green wire - Signal out) moves between the two. As the throttle opens more, resistance between the orange wire (VREF) & the green wire (Signal out) decreases. The resistance between the green wire (Signal Out) & black/wire (Signal Ground) wire increases. This causes the Signal Out voltage to increase with reference to Signal Ground. Signal Ground is wired to common ground through the computer.

 

[65ShelbyClone]

Alright cool, it's like I thought......but is the vref 12v or 5v?

 

[jrichker]

Alright cool, it's like I thought......but is the vref 12v or 5v?

VREF is 5 volts supplied by the computer.

 

[65ShelbyClone]

Cool, thanks.