The Electronic Throttle Control(ETC) system is made of the components throttle body, Throttle Position Sensor(TPS) 1&2 and Accelerator Position Sensor(APS) 1&2. The APS is mounted in the accelerator pedal to detect the opening angle of the accelerator pedal. It has 2 sensors to detect the accelerator position and a malfunction of the accelerator position sensor. The PCM judges the current opening angle of the accelerator pedal from APS1&2, and the PCM controls the throttle motor based on these signals.
Checking output signals from APS 1 under detecting condition, if output signals are below the threshold, PCM sets P2122. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till 1 driving cycle.
Item
Detecting Condition
Possible Cause
DTC Strategy
? This code detects a continuous short to ground or open in either the circuit or the sensor (0-100%)
? Poor connection
? Open or short to ground in Power circuit
? Open or short to ground in Signal Circuit
? Faulty APS
? Faulty PCM
EnableConditions
? Ignition "ON"
Threshold Value
? APS1 < 0.125V
Diagnosis Time
? Continuous
MIL On Condition
? 1 Driving Cycle
Pedal Position
Output Voltage(V) [Vref = 5.0V]
APS1
APS2
C.T
0.7 ~ 0.8V
0.275 ~ 0.475V
W.O.T
3.8 ~ 4.4V
1.75 ~ 2.35V
Fig.1) This is a signal waveform of APS 1 & 2 which shows that APS 2 increases voltage just half of APS 1 voltage increase when accelerating.