Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Throttle/pedal position
sensor/switch ”a” circuit / Circuit description
Toyota Corolla (E120): Circuit description
The throttle position sensor is mounted in the throttle body and detects the throttle valve opening angle.
When the throttle valve is fully closed, a voltage of approximately 0.3 To 1.0 V is applied to terminal vta of the ecm. The voltage applied to terminal vta of the ecm increases in proportion to the opening angle of the throttle valve and becomes approximately 3.2 To 4.9 V when the throttle valve is fully opened. The ecm judges the vehicle driving conditions from these signals input from terminal vta, uses them as one of the conditions for deciding the air–fuel ratio correction, power increase correction and fuel–cut control etc.
Hint
: after confirming dtcs, confirm the throttle valve opening percentage and closed throttle position switch condition using the hand–held tester or the obd ii scan tool.
Monitor description
The throttle position sensor varies its resistance with the throttle valve angle. The ecm applies a regulated reference voltage to the throttle position sensor “+: vc” terminal and calculates the angle of the throttle valve based on the voltage present at the throttle position sensor “signal: vta” terminal.
When the throttle valve is near the fully closed position, the output voltage of the throttle position sensor is low. When it is near the fully open position, the output voltage is high.
If the ecm detects that the output voltage of the throttle position sensor is out of the normal range, the ecm interprets this as a malfunction in the throttle position sensor and sets a dtc.
Monitor strategy
Typical enabling condition
Typical malfunction thresholds
Component operating range
Wiring diagram
Other materials:
Wiper & washer
Preparation
Sst
Recomended tools
Equipment
...
Clutch
Preparation
Sst
Recomended tools
Equipment
Lubricant
...
Circuit description
The actuator motor is operated by signals from the cruise control ecu assy.
Acceleration and deceleration
signals are transmitted by changes in the duty ratio (see below).
Duty ratio:
the duty ratio is the ratio of the period of continuity in one cycle. For
example, if a is the period of co ...