Troubleshooting
DTC P2123 THROTTLE/PEDAL POSITION SENSOR/SWITCH "D" CIRCUIT HIGH INPUTCIRCUIT DESCRIPTION
HINT:
- This is the repair procedure of "accelerator pedal position sensor".
- This electrical throttle system does not use throttle cable.
- This accelerator pedal position sensor is non-contact type.
DTC Detection Condition:
The accelerator pedal position sensor is mounted in the accelerator pedal to detect the opening angle of the accelerator pedal. Since this sensor is electronically controlled with hall elements, accurate control and reliability can be obtained. It has 2 sensors to detect the accelerator position and a malfunction of the accelerator position sensor.
In the accelerator pedal position sensor, the voltage applied to pedal terminals VPA and VPA2 of the ECM changes between 0 V and 5 V, in proportion to the opening angle of the accelerator pedal. The VPA is a signal to indicate the actual accelerator pedal opening angle which is used for the engine control, and the VPA2 is a signal to indicate the information about the opening angle which is used for detecting a malfunction. The ECM judges the current opening angle of the accelerator pedal from these signals input from terminals VPA and VPA2, and the ECM controls the throttle motor based on these signals.
HINT: After confirming DTC "P2120, P2122, P2123, P2125, P2127, P2128 and P2138", use the hand-held tester or the OBD II scan tool to confirm the accelerator pedal position sensor output voltage.
Wiring Diagram:
INSPECTION PROCEDURE
HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.
Step 1:
Step 2 - 3:
Step 3 (Continued) - 5:
Hand-held tester
Step 1:
Step 2 - 4:
OBD II scan tool (excluding hand-held tester)