DTC P2120-12: Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Battery; DTC P2120-14: Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Ground or Open; DTC P2120-1C: Throttle/Pedal Position Sensor/Switch "D" Circuit Voltage Out of Range; DTC P2120-1F: Throttle/Pedal Position Sensor/Switch "D" Circuit Intermittent; DTC P2120-99: Throttle/Pedal Position Sensor/Switch "D" Exceeded Learning Limit; DTC P2125-12: Throttle/Pedal Position Sensor/Switch "E" Circuit Short to Battery; DTC P2125-14: Throttle/Pedal Position Sensor/Switch "E" Circuit Short to Ground or Open; DTC P2125-1F: Throttle/Pedal Position Sensor/Switch "E" Circuit Intermittent; DTC P2138-2B: Throttle/Pedal Position Sensor/Switch "D"/"E" Voltage Correlation Signal Cross Coupled [12/2019 - 10/2022]: Description

HINT:

This Electronic Throttle Control System (ETCS) does not use a throttle cable.
These DTCs relate to the accelerator pedal position sensor.

The accelerator pedal position sensor is built into the accelerator pedal sensor assembly and has 2 sensor circuits: VPA (main) and VPA2 (sub). This sensor is a non-contact type sensor and 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 voltage, which is applied to terminals VPA and VPA2 of the ECM, varies between 0.5 V and 4.75 V in proportion to the operating angle of the accelerator pedal (throttle valve). A signal from VPA indicates the actual accelerator pedal opening angle (throttle valve opening angle) and is used for engine control. A signal from VPA2 conveys the status of the VPA circuit and is used to check the accelerator pedal position sensor itself.

The ECM monitors the actual accelerator pedal opening angle (throttle valve opening angle) through the signals from VPA and VPA2, and controls the throttle actuator according to these signals.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P2120-12	Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Battery	VPA is 4.8 V or higher for 2 seconds or more (1 trip detection logic).	Accelerator pedal sensor assembly Open in EPA circuit Short in VPA circuit ECM	Comes on	DTC stored	SAE Code: P2123 DTC for Mexico Models: - Applies
P2120-14	Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Ground or Open	VPA is 0.4 V or less for 0.5 seconds or more when the accelerator pedal is depressed (1 trip detection logic).	Accelerator pedal sensor assembly Open in VCPA circuit Open or ground short in VPA circuit ECM	Comes on	DTC stored	SAE Code: P2122 DTC for Mexico Models: - Applies
P2120-1C	Throttle/Pedal Position Sensor/Switch "D" Circuit Voltage Out of Range	Difference between VPA and VPA2 is greater than or equal to the specified value for 0.5 seconds (1 trip detection logic).	Accelerator pedal sensor assembly ECM	Comes on	DTC stored	SAE Code: P2121 DTC for Mexico Models: - Applies
P2120-1F	Throttle/Pedal Position Sensor/Switch "D" Circuit Intermittent	VPA fluctuates rapidly beyond the upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic).	Accelerator pedal sensor assembly Accelerator pedal sensor assembly circuit ECM	Comes on	DTC stored	SAE Code: P2120 DTC for Mexico Models: - Applies
P2120-99	Throttle/Pedal Position Sensor/Switch "D" Exceeded Learning Limit	Difference between VPA and VPA2 is less than 0.4 V, or higher than 1.2 V (learned value of accelerator off position) (1 trip detection logic).	Accelerator pedal sensor assembly ECM	Comes on	DTC stored	SAE Code: P2121 DTC for Mexico Models: - Applies
P2125-12	Throttle/Pedal Position Sensor/Switch "E" Circuit Short to Battery	Both of the following conditions are met for 2 seconds or more (1 trip detection logic): (a) VPA2 is 4.8 V or higher. (b) VPA is between 0.4 V and 3.45 V.	Accelerator pedal sensor assembly Open in EPA2 circuit Short in VPA2 circuit ECM	Comes on	DTC stored	SAE Code: P2128 DTC for Mexico Models: - Applies
P2125-14	Throttle/Pedal Position Sensor/Switch "E" Circuit Short to Ground or Open	VPA2 is 1.2 V or less for 0.5 seconds or more when the accelerator pedal is depressed (1 trip detection logic).	Accelerator pedal sensor assembly Open in VCP2 circuit Open or ground short in VPA2 circuit ECM	Comes on	DTC stored	SAE Code: P2127 DTC for Mexico Models: - Applies
P2125-1F	Throttle/Pedal Position Sensor/Switch "E" Circuit Intermittent	VPA2 fluctuates rapidly beyond the upper and lower malfunction thresholds for 0.5 seconds or more (1 trip detection logic).	Accelerator pedal sensor assembly Accelerator pedal sensor assembly circuit ECM	Comes on	DTC stored	SAE Code: P2125 DTC for Mexico Models: - Applies
P2138-2B	Throttle/Pedal Position Sensor/Switch "D"/"E" Voltage Correlation Signal Cross Coupled	Difference between VPA and VPA2 is 0.02 V or less for 2 seconds or more (1 trip detection logic).	Accelerator pedal sensor assembly Short between VPA and VPA2 circuits ECM	Comes on	DTC stored	SAE Code: P2138 DTC for Mexico Models: - Applies

HINT:

When any of these DTCs are output, check the accelerator pedal position sensor voltage using the GTS. Enter the following menus: Powertrain / Engine / Data List / Accelerator Position Sensor No. 1 Voltage and Accelerator Position Sensor No. 2 Voltage.

Trouble Area	Accelerator Pedal Fully Released		Accelerator Pedal Fully Depressed
Trouble Area	Accelerator Position Sensor No. 1 Voltage	Accelerator Position Sensor No. 2 Voltage	Accelerator Position Sensor No. 1 Voltage	Accelerator Position Sensor No. 2 Voltage
Open in VC circuit	0 to 0.2 V	0 to 0.2 V	0 to 0.2 V	0 to 0.2 V
Open or ground short in VPA circuit	0 to 0.2 V	1.2 to 2.0 V	0 to 0.2 V	3.4 to 4.75 V
Open or ground short in VPA2 circuit	0.5 to 1.1 V	0 to 0.2 V	2.6 to 4.5 V	0 to 0.2 V
Open in EPA circuit	4.5 to 4.98 V	4.5 to 4.98 V	4.5 to 4.98 V	4.5 to 4.98 V
Normal condition	0.5 to 1.1 V	1.2 to 2.0 V	2.6 to 4.5 V	3.4 to 4.75 V

HINT:

Accelerator pedal positions are expressed as voltages.