Circuit Description

Throttle Position (TP) sensor is mounted on throttle body and detects throttle opening angle. When throttle valve is closed, approximately 0.3-0.8 volt is applied to TP input circuit. Voltage will increase in proportion to amount of throttle valve opening angle. At Wide Open Throttle (WOT), TP input circuit voltage is approximately 3.2-4.9 volts. PCM judges vehicle driving condition from TP sensor input and determines air-fuel correction, power increase correction and fuel-cut control. DTC P0120 will set when:

TP sensor input to PCM is greater than 1.0 volt with throttle valve closed.
TP sensor input to PCM is less than 4.9 volts at WOT.

NOTE: An open in idle input circuit will NOT set DTC P0120 or P0121. If DTCs P0105, P0110, P0115 and P0120 are set together, sensor ground circuit may be at fault.