Hyundai Elantra HD: Throttle Position Sensor (TPS). Description and Operation
Function And Operation Principle
The Throttle Position Sensor (TPS) is mounted on the throttle body and
detects the opening angle of the throttle plate. The TPS has a variable resistor
(potentiometer) whose characteristic is the resistance changing according to
the throttle angle. During acceleration, the TPS resistance between the reference
5V and the signal terminal decreases and output voltage increases; during deceleration,
the TPS resistance increases and TPS output voltage decreases. The ECM supplies
a reference 5V to the TPS and the output voltage increases directly with the
opening of the throttle valve. The TPS output voltage will vary from 0.2~0.8V
at closed throttle to 4.3~4.8V at wide-open throttle. The ECM determines operating
conditions such as idle (closed throttle), part load, acceleration/deceleration,
and wide-open throttle from the TPS. Also The ECM uses the Manifold Absolute
Pressure Sensor (MAPS) signal along with the TPS signal to adjust fuel injection
duration and ignition timing.
