Circuit Description
WARNING: This page is about a different car, the 2007 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The throttle position (TP) sensor 1 and sensor 2 are located within the throttle body assembly. Each sensor has the following circuits:
- A 5-volt reference circuit
- A low reference circuit
- A signal circuit
This provides the engine control module (ECM) with a signal voltage proportional to the throttle plate movement. TP sensor 1 signal voltage at closed throttle is near the 5-volt reference and decreases as the throttle plate is opened. TP sensor 2 signal voltage at closed throttle is near the low reference and increases as the throttle plate is opened. If the ECM detects the TP sensor 1 signal voltage is more than the predicted range, DTC P0123 sets.