3.
Monitor the "TPS" parameters on the scantool.
The Throttle Position Sensor (TPS) is mounted on the throttle body and detects the opening angle of the throttle plate.The TPS has a variable resistor (potentiometer) whose characteristic is the resistance changing according to the throttle angle. During acceleration, the TPS resistance between the reference 5V and the signal terminal decreases and output voltage increases; during deceleration, the TPS resistance increases and TPS output voltage decreases.The ECM supplies a reference 5V to the TPS and the output voltage increases directly with the opening of the throttle valve. The TPS output voltage will vary from 0.2~0.8V at closed throttle to 4.3~4.8V at wide-open throttle.The ECM determines operating conditions such as idle (closed throttle), part load, acceleration/deceleration, and wide-open throttle from the TPS. Also The ECM uses the Mass Air Flow Sensor (MAFS) or Manifold Absolute Pressure Sensor (MAPS) signal along with the TPS signal to adjust fuel injection duration and ignition timing.
If the difference between modeled relative load and measured relative load is over the threshold value according to throttle position under enable conditions, ECM sets DTC P0124.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Rationality check | ● Poor connection ● TPS ● ECM |
Enable Conditions | ● Rate of change of throttle angle 〈 0.1221% ● Engine speed 〉 600rpm ● Coolant temperature 〉 75℃ ● Rate of change of predicted eng. load 〈 15% ● Altitude 〉 0m ● Time in idling 〉 30s | |
Threshold Value | ● Difference between modeled relative load and measured relative load 〉 threshold f(throttle position) | |
Diagnostic Time | ● 2.5sec | |
MIL ON Condition | ● DTC only |
ITEM | Specification |
TPS Resistance (kΩ) | 2kΩ ± 20% (20℃) |
Connect scantool to Data Link Connector(DLC).
Warm up the engine to normal operating temperature.
Monitor the "TPS" parameters on the scantool.
Is parameter displayed within specifications?
▶ Fault is intermittent caused by poor contact in the sensor’s and/or ECM’s connector or was repaired and ECM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, tamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of vehicle Repair" procedure.
▶ Go to "Terminal and Connector Inspection" procedure.
Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
Has a problem been found?
▶ Repair as necessary and go to "Verification of vehicle Repair" procedure.
▶ Go to "TPS circuit inspection" procedure.
Ignition "OFF"
Disconnect TPS connector.
Ignition "ON"
Measure voltage between terminal "1","2" and "3" of sensor harness connector and chassis ground
Specification :
Terminal 1 : Approx. 5V
Terminal 2 : Approx. 5V
Terminal 3 : Approx. 0V
Is the measured voltage within specifications?
▶ Go to "Component inspection" procedure.
▶ Check for Open or Short in TPS circuit. Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
Check TPS.
Ignition "OFF"
Disconnect TPS connector
Measure resistance terminal 2 and 3 of TPS Component side connector.
ITEM | Specification |
TPS Resistance (kΩ) | 2kΩ ± 20% (20℃) |
Is the measured resistance within specifications?
▶ Go to "Check ECM" procedure.
▶ Check TPS for contamination, deterioration, or damage. Substitute with a known-good TPS andcheck for proper operation. If the problem is corrected, replace TPS and then go to "Verification of Vehicle Repair" procedure.
Check ECM.
Ignition "OFF"
Connect the scantool and select "Simulation SCAN" in the menu.
Connect channel A of scantool with terminal 1 of TPS harness connector, and key "ON".
Simulate voltage at signal line.
Is TPS signal value changed according to simulation voltage?
▶ Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination,deterioration, or damage. Repair or replace as necessary and then go to "Verification of VehicleRepair" procedure..
▶ Substitute with a known-good ECM and check for proper operation.
▶If the problem is corrected, replace ECM and then go to "Verification of Vehicle Repair" procedure.
After a repair, it is essential to verify that the fault has been corrected.
Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
Clear the DTCs and Operate the vehicle within DTC Enable conditions in General information.
Are any DTCs present ?
▶ Go to the applicable troubleshooting procedure.
▶ System is performing to specification at this time.
