Hyundai Ioniq (AE): Engine Control System / Accelerator Position Sensor (APS). Description and operation
Accelerator Position Sensor (APS) is installed on the accelerator pedal module and detects the rotation angle of the accelerator pedal. The APS is one of the most important sensors in engine control system, so it consists of the two sensors which adapt individual sensor power and ground line. The second sensor monitors the first sensor and its output voltage is half of the first one. If the ratio of the sensor 1 and 2 is out of the range (approximately 1/2), the diagnostic system judges that it is abnormal.

Inspection1.Connect the GDS on the Data Link Connector (DLC).2.Measure the output voltage of the RPS at idle and various engine speed. Condition Output Voltage (V) Idle Approx.
Specification
Accelerator Position
Output Voltage (V)
APS1
APS2
C.
Other information:
Description The photo sensor is located at the center of the defrost nozzles.The photo sensor contains a photovoltaic (sensitive to sunlight) diode. The solar radiation received by its light receiving portion, generates an electromotive force in proportion to the amount of radiation received which is transferred to the automatic temperature control
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