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 throttle body contains the actuator, the throttle plate and the throttle position sensor (potentiometer), which are integrated in one housing. The actuator consists of a DC motor with a two-stage gear. The opening angle of the throttle valve is detected by the throttle position sensor which is mounted on the throttle body. And it provides feedback to the ECM to control the throttle motor in order to control the throttle valve opening angle properly in response to the driving condition.
Checking throttle valve return state under detecting condition, if an output signal is within the threshold value for more than designated time, PCM sets P1523.
Item | Detecting Condition | Possible cause |
DTC Strategy | ● Monitor throttle valve return state | ● Carbon in throttle ● Broken Throttle return spring ● throttle sticky ● throttle icy |
EnableConditions | ● ETC Power Control Mode ● TPS 1 & 2 = normal ● Sensor Supply voltage = Normal | |
Threshold value | ● The throttle did not return to default range within 1 to 4 seconds of turning off. That is, (TPS1's signal > 0.9V AND TPS1's signal < 1.85V) or (TPS2's signal < 1.85V AND TPS2's signal >0.9V) when the power to the ETC motor is turned off. | |
DiagnosisTime | ● Continuous | |
MIL On Condition | ● DTC only (NO MIL ON) |
Throttle opening ( ° ) | Output voltage (V) [Vref = 5.0V] | |
TPS1 | TPS2 | |
0° | 0.0V | 5.0V |
10° | 0.5V | 4.5V |
20° | 0.9V | 4.1V |
30° | 1.4V | 3.6V |
40° | 1.8V | 3.2V |
50° | 2.3V | 2.7V |
60° | 2.7V | 2.3V |
70° | 3.2V | 1.8V |
80° | 3.6V | 1.4V |
90° | 4.1V | 0.9V |
100° | 4.5V | 0.5V |
110° | 5.0V | 0.0V |
Check DTC Status
Connect scantool to Data Link Connector(DLC).
IG "ON".
Select "Diagnostic Trouble Codes(DTCs)" mode, and then Press F4(DTAL) to check DTC's information from the DTCs menu
Read "DTC Status" parameter.
Is parameter displayed "Present fault"?
▶ Go to "System inspection" procedure.
▶ Fault is intermittent caused by poor contact in the sensor’s and/or PCM’s connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
Visual Inspection
IG "OFF".
Check throttle valve after removing air duct.
Carbon deposit.
Throttle icy
Broken return spring.
Throttle sticky
Is the throttle valve return O.K ?
▶ Thoroughly check that something interferes throttle movement and perform ETS Initialization as follows and then, go to "Verification of Vehicle Repair" procedure.
▶ Repair or replace as necessary and then, do ETS Initialization" as follows. then, go to "Verification of Vehicle Repair" procedure.
※ Procedure of ETS Initialization
1. Erase the trouble codes on PCM
2. Turn the ignition key off and keep this condition until the main relay is turned off.(It will takes 10sec.)
3. Turn ignition key on more than 1second to record the throttle motor position on the EEPROM
After a repair, it is essential to verify that the fault has been corrected.
Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode
Press F4(DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions
Read "DTC Status" parameter
Is parameter displayed "History(Not Present) fault"?
▶ System performing to specification at this time. Clear the DTC.
▶ Go to the applicable troubleshooting procedure.