
Hint:
This dtc relates to the throttle position (tp) sensor.
Description
Refer to dtc p0120 (see page es-114).

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.
For each throttle opening angle, a specific voltage difference is expected between the outputs of vta1 and vta2. If the output voltage difference between the two signals deviates from the normal operating range, the ecm interprets this as a malfunction of the tp sensor. The ecm illuminates the mil and sets the dtc.
If the malfunction is not repaired successfully, the dtc is set 2 seconds after the engine is next started.
Monitor strategy

Typical enabling conditions

Typical malfunction thresholds
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Fail-safe
When this dtc, as well as other dtcs relating to etcs (electronic throttle control system) malfunctions, is set, the ecm enters fail-safe mode. During fail-safe mode, the ecm cuts the current to the throttle actuator off, and the throttle valve is returned to a 6° throttle angle by the return spring. The ecm then adjusts the engine output by controlling the fuel injection (intermittent fuel-cut) and ignition timing, in accordance with the accelerator pedal opening angle, to allow the vehicle to continue at a minimal speed. If the accelerator pedal is depressed firmly and gently, the vehicle can be driven slowly.
Fail-safe mode continues until a pass condition is detected, and the ignition switch is then turned off.
Inspection procedure
Hint:
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

Throttle / pedal position sensor / switch "A"
Insufficient coolant temperature for closed loop fuel controlDtc check / clear
Notice:
When the diagnosis system is changed from normal
mode to check mode or vice versa, all dtcs and freeze
frame data recorded in normal mode are erased. Before
changing modes, always check and make a note of any
dtcs and freeze frame data.
Hint:
Dtcs which are stored in the ecm can be ...
If you think something is
wrong
If you notice any of the following
symptoms, your
vehicle probably needs
adjustment or repair. Contact
your Toyota dealer as
soon as possible.
Visible symptoms
Fluid leaks under the vehicle
(Water dripping from the air
conditioning after use is normal.)
Flat-looking tires or uneven
tire wear
...
Diagnosis system
Description
When troubleshooting on-board diagnostic (obd
ii) vehicles, the vehicle must be connected to the
obd ii scan tool (complying with sae j1987).
Various data output from the vehicle's ecm can
then be read.
Obd ii regulations require that the vehicle's onboard
computer ...