Accelerator position sensor (APP)
Target:
*Detection of accelerator pedal position
* Transmission of this signal to the ECU (electronic control unit) of the engine or transmission
APP sensor types:
* Potentiometric: Using a variable resistor to measure pedal position
* Hall Effect: Using a magnetic field to measure pedal position
Location:
* Usually mounted on the accelerator pedal or throttle body
Operation:
* When the driver presses the accelerator pedal, the APP sensor converts the pedal position into an electrical signal.
* The signal is transmitted to the ECU along with other engine and transmission data.
* The ECU uses the APP signal to determine the required throttle position to maintain proper acceleration and speed control.
APP sensor faults:
* Trouble Codes (DTC): The ECU may set DTCs indicating a malfunction of the APP sensor.
* Symptoms:
* Uneven acceleration or jerking
* Inability to start the engine
*Limited engine power
*Check Engine light comes on
Diagnostics:
* Read trouble codes (DTC)
*Check APP signal using diagnostic tool
* Checking wiring and connections
Consequences of the malfunction:
*A faulty APP sensor can cause problems with fuel efficiency, engine power and transmission performance.
* It is important to promptly diagnose and repair a faulty APP sensor to ensure proper vehicle operation.