Sensors tps

Throttle Position Sensor

note:
potentiometer have a sliding variable resistor
that slides moving the throttle butterfly
Using a switch type TPS, having a 5volt supply conected right and earthed varible resistor should operate from 0 to 90 degrees, as the throttle is opened letting more air in, the voltage is increased ...

Note: round type sensors indicate that is a lener tps, switch type sensors are square in shape .

The varible resistor located in the tps unit, which sits on a number of sliding contact plates which are changed when the throttle increases and decreases from idle to wot (wide open throttle ), the more the throttle is opened the higher the voltage will be... 0.5v at idle - 4.02v at wot

Back probing a tps

having the voltmeter set to dc volts, and having a pin inserted down insulation, with the ignition turned to "On", i got a reading of 0 volts
Withe the engine still in the "ON' position, move the throttle to a half open position getting a reading of 2.52 volts
With the throttle at wot (wide open throttle) the voltage there was 5 .12volts

TPS operates with a input voltage of 5 volts, normally a grey wire. A signal wire to the ECU, somtimes a fourth wire to ensure that the signal to the ECU is a correct reading. As the valve angle changes due to the driver acclerating or decclerating, the ECU calulates and determines how much fuel is needed to deliver a good air/fuel ratio to maximize engine performance.

Throttle position switch

As before back probe the TPS

only having the ignition in the "ON" position, using a mutli meteri found which wires changed at idle and wot, the colour of the idle wire was Blue, the wot wire was Green

idle ranged from : 0.7 to 1v

wot ranged from :4.3 to 5 v

part throtle ranged from :2.5 to 3.8v