Throttle Position Sensor (TPS)

The TPS is a variable mechanical resistor connected either directly to the throttle shaft linkage. The TPS has 3 wires connected to it. One is connected to a 5-volt reference voltage supply from ECM. The second is connected to ECM ground and the third is the signal return which is monitored by ECM. The voltage signal from the TPS varies from closed throttle (.5-1.0 volt) to wide open throttle (4.5-5 volts). This signal is used by ECM for determining control of fuel, idle speed, spark timing and converter clutch. A problem in the TPS circuit may set a related trouble code.