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Throttle Position (TP) Sensor

The Throttle Position (TP) sensor is mounted on the throttle body assembly. The sensor is comprised of two potentiometers with common supply and ground circuits, and independent signal circuits. As the throttle opens, the signal wire on sensor 1 reads a higher voltage, and the voltage on signal wire for sensor 2 decreases. This is used as a feedback device to allow the ECM to compare the throttle body's present location to where it is commanded to be.

This sensor is also used with the throttle motor to correctly position the throttle butterfly to maintain the vehicle speed commanded by the cruise control input. An error with the TPS system will disable cruise operation.