Toyota 2GR-FE Manual page 326

ES–170
Throttle Position
Sensor
ES
IC No. 1
IC No. 2
HINT:
This DTC relates to the Throttle Position (TP) sensor.
DTC No.
P0121
MONITOR DESCRIPTION
The ECM uses the TP sensor to monitor the throttle valve opening angle.
This sensor transmits two signals: VTA1 and VTA2. VTA1 is used to detect the throttle opening angle and
VTA2 is used to detect malfunctions in VTA1. The ECM performs several checks to confirm the proper
operation of the TP sensor and VTA1.
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
Sensor Output Voltage (V)
Magnet
ECM
VC
VTA1
VTA2
E2
Magnet
DTC Detection Condition
Difference between VTA1 and VTA2 voltages less than
0.8 V, or more than 1.6 V for 2 seconds (1 trip detection
logic)
Fail Safe Angle
5.0
VTA2
2.55
2.25
0.93
0.69
6°
0°
Throttle Valve Opening Angle (degrees)
Note:
The throttle valve opening angle detected by the sensor terminal
VTA1 is expressed as percentages.
Between 10 % and 24 %: Throttle valve fully closed
Between 64 % and 96 %: Throttle valve fully open
Approximately 19 %: Fail-safe angle (6°)
TP sensor (built into throttle body)
VTA1
Usable Range
84°
Trouble Area
A019802E31