The 3-wire Throttle Position Sensor (TPS) provides the Powertrain Control Module (PCM) with an input signal (voltage) that represents the throttle blade position of the throttle body. The sensor is connected to the throttle blade shaft. As the position of the throttle blade changes, the output voltage of the TPS changes.
The PCM supplies approximately 5 volts to the TPS. The TPS output voltage (input signal to the PCM) represents the throttle blade position. The PCM receives an input signal voltage from the TPS. This will vary in an approximate range of from .26 volts at minimum throttle opening (idle), to 4.49 volts at wide open throttle. Along with inputs from other sensors, the PCM uses the TPS input to determine current engine operating conditions. In response to engine operating conditions, the PCM will adjust fuel injector pulse width and ignition timing.
Removal & Installation
3.7L & 4.7L Engines
- Before servicing the vehicle, refer to the Precautions Section.
- Remove air resonator tube at throttle body.
- Disconnect the Throttle Position Sensor (TPS) electrical connector.
- Remove 2 TPS mounting screws.
- Remove the TPS.
The throttle shaft end of throttle body slides into a socket in TPS. The TPS must be installed so that it can be rotated a few degrees. (If sensor will not rotate, install sensor with throttle shaft on other side of socket tangs). The TPS will be under slight tension when rotated.
- Install the TPS and retaining screws.
- Tighten screws to 60 inch lbs. (7 Nm).
- Connect the TPS electrical connector to TPS.
- Manually operate the throttle (by hand) to check for any TPS binding before starting engine.
- Install air cleaner tube to throttle body.
3.7L & 4.7L Engines
- Visually check the connector, making sure it is attached properly and that all of the terminals are straight, tight and free of corrosion.
- Connect the DVOM between the center terminal and sensor ground.
- With the ignition key to the ON position and the engine off, check the output voltage at the center terminal wire of the connector.
- Check the output voltage at idle and at Wide Open Throttle (WOT).
- The TPS output voltage should be about 0.38-1.20 volts. At WOT, the output voltage should be about 3.1-4.4 volts.
- The output voltage should gradually increase as the throttle plate moves slowly from idle to WOT.
- If the voltage is not as stated, replace the TPS.
- Turn the ignition off.
- Disconnect the TP Sensor harness connector.
- Ignition on, engine not running.
- Measure the voltage on the (F855) 5-volt Supply circuit in the TP Sensor harness connector.
If the voltage is not between 4.5-5.2, repair the (F855) 5-volt Supply circuit.