Accel Position Sensor [APS]
The Accelerator Pedal Sensor (APS) is a very important sensor which controls the fuel amount by transmitting the driver's accelerating intention to the ECM. The APS is divided into APS 1, 2 because its reliability is important. The APS 1, 2 are composed with the independent power and ground. APS 2 shows the 1/2 output of the APS1 and decides the fault if the ratio of APS 1, 2 is different. When the APS 1 is out of order, the signal of APS 2 can be substituted instead of APS 1 and vise versa. The ECM is activated by power supply. Signals from several sensors such as CKPS and APS is inputted to ECM.
Comparing inputted signals with control LOGIC are saved at micro controller and EEPROM, the ECM controls engine as actuating injectors, solenoids and relays. To guarantee accurate control, the ECM performs SELF TEST, DIAGNOSIS of several sensors and actuators. If serious trouble which affects vehicle performance occurs, the ECM sets DTCs. At certain cases, ECM shuts down whole systems in order to prevent dangerous situation due to incorrect control.
The ECM provides a 5 volt reference voltage to the Acceleration Position Sensor (APS). The ECM monitors reference voltage deviation from the power supply circuit of the APS.