DTC P0120-P0123, P0220, P0222, P0223, P2135; Throttle Pedal Position Sensor / Switch "A" Circuit [08/2013 - 08/2016]: Description

WARNING: This page is about a different variant/trim than selected.

HINT:

These DTCs relate to the throttle position sensor.

The throttle position sensor is mounted on the throttle body assembly and detects the opening angle of the throttle valve. This sensor is a non-contact type sensor. It uses Hall-effect elements in order to yield accurate signals even in extreme driving conditions, such as at high speeds as well as very low speeds.

The throttle position sensor has 2 sensor circuits, VTA1 and VTA2 each of which transmits a signal. VTA1 is used to detect the throttle valve angle and VTA2 is used to detect malfunctions in VTA1. The sensor signal voltages vary between 0 V and 5 V in proportion to the throttle valve opening angle, and are transmitted to the VTA1 and VTA2 terminals of the ECM.

As the valve closes, the sensor output voltage decreases and as the valve opens, the sensor output voltage increases. The ECM calculates the throttle valve opening angle according to these signals and controls the throttle actuator in response to driver inputs. These signals are also used in calculations such as air fuel ratio correction, power increase correction and fuel-cut control.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P0120	Throttle Pedal Position Sensor / Switch "A" Circuit	The output voltage of VTA1 quickly fluctuates beyond the lower and upper malfunction thresholds for 2 seconds or more (1 trip detection logic).	Throttle position sensor (throttle body assembly) ECM	Comes on	DTC stored	DTC for Mexico Models - Applies
P0121	Throttle Pedal Position Sensor / Switch "A" Circuit Range / Performance	The difference between the output voltages of VTA1 and VTA2 is less than 0.8 V, or higher than 1.6 V for 2 seconds (1 trip detection logic).	Throttle position sensor (throttle body assembly) Throttle position sensor circuit ECM	Comes on	DTC stored	DTC for Mexico Models - Applies
P0122	Throttle / Pedal Position Sensor / Switch "A" Circuit Low Input	The output voltage of VTA1 is 0.2 V or less for 2 seconds or more (1 trip detection logic).	Throttle position sensor (throttle body assembly) Short in VTA1 circuit Open in VCTA circuit ECM	Comes on	DTC stored	DTC for Mexico Models - Applies
P0123	Throttle / Pedal Position Sensor / Switch "A" Circuit High Input	The output voltage of VTA1 is 4.535 V or higher for 2 seconds or more (1 trip detection logic).	Throttle position sensor (throttle body assembly) Open in VTA1 circuit Open in ETA circuit Short between VCTA and VTA1 circuits ECM	Comes on	DTC stored	DTC for Mexico Models - Applies
P0220	Throttle / Pedal Position Sensor / Switch "B" Circuit	The output voltage of VTA2 quickly fluctuates beyond the lower and upper malfunction thresholds for 2 seconds or more (1 trip detection logic).	Throttle position sensor (throttle body assembly) ECM	Comes on	DTC stored	DTC for Mexico Models - Applies
P0222	Throttle / Pedal Position Sensor / Switch "B" Circuit Low Input	The output voltage of VTA2 is 1.75 V or less for 2 seconds or more (1 trip detection logic).	Throttle position sensor (throttle body assembly) Short in VTA2 circuit Open in VCTA circuit ECM	Comes on	DTC stored	DTC for Mexico Models - Applies
P0223	Throttle / Pedal Position Sensor / Switch "B" Circuit High Input	The output voltage of VTA2 is 4.8 V or higher, and VTA1 is between 0.2 V and 2.02 V for 2 seconds or more (1 trip detection logic).	Throttle position sensor (throttle body assembly) Open in VTA2 circuit Short between VCTA and VTA2 circuits ECM	Comes on	DTC stored	DTC for Mexico Models - Applies
P2135	Throttle / Pedal Position Sensor / Switch "A" / "B" Voltage Correlation	Either of the following conditions is met (1 trip detection logic): (a) The difference between the output voltages of VTA1 and VTA2 is 0.02 V or less for 0.5 seconds or more. (b) The output voltage of VTA1 is 0.2 V or less, and VTA2 is 1.75 V or less for 0.4 seconds or more.	Short between VTA1 and VTA2 circuits Open in ETA circuit Throttle position sensor (throttle body assembly) ECM	Comes on	DTC stored	DTC for Mexico Models - Applies

HINT:

When any of these DTCs are output, check the throttle valve opening angle using the Techstream. Enter the following menus: Powertrain / Engine and ECT / Data List / Gas Throttle / Throttle Position No. 1 and Throttle Position No. 2.

Throttle Position No. 1 is the VTA1 signal, and Throttle Position No. 2 is the VTA2 signal.

Reference (Normal Condition)

Techstream Display	Accelerator Pedal Fully Released	Accelerator Pedal Fully Depressed
Throttle Position No. 1	0.5 to 1.1 V	3.2 to 4.8 V
Throttle Position No. 2	2.1 to 3.1 V	4.6 to 4.98 V