Throttle Position Sensor: Testing and Inspection

DESCRIPTION
The throttle position sensor responds to the accelerator pedal movement. This sensor is a kind of potentiometer which transforms the throttle position into output voltage, and emits the voltage signal to the ECM. In addition, the sensor detects the opening and closing speed of the throttle valve and feeds the voltage signal to the ECM.
Idle position of the throttle valve is determined by the ECM receiving the signal from the throttle position sensor. This controls engine operation such as fuel cut. The throttle position sensor unit contains a built-in "Wide open and closed throttle position switch".




DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE

OVERALL FUNCTION CHECK
Use this procedure to check the overall function of the throttle position sensor. During this check, a DTC might not be confirmed.

WITH CONSULT
1. Start engine and warm it up sufficiently.
2. Turn ignition switch "OFF" and wait at least 5 seconds.
3. Turn ignition switch "ON".
4. Select "MAN U TRIG" and "HI SPEED" in "DATA MONITOR" mode with CONSULT.
5. Select "THRTL POS SEN" and "ABSOL TH/PO SEN" in "DATA MONITOR" mode with CONSULT.




6. Press RECORD on CONSULT SCREEN at the same time accelerator pedal is depressed.




7. Print out the recorded data and check the following:
- The voltage when accelerator pedal fully released is 0.3 - O.7V.
- The voltage rise is linear in response to accelerator pedal depression.
- The voltage when accelerator pedal fully depressed is approximately 4V.

OR

WITH NO TOOLS
1. Start engine and warm it up sufficiently.
2. Turn ignition switch "OFF" and wait at least 5 seconds.
3. Turn ignition switch "ON".




4. Check the voltage between ECM terminal (23) and (43) (ground) and check the following:
- The voltage when accelerator pedal fully released is 0.3 - O.7V.
- The voltage rise is linear in response to accelerator pedal depression.
- The voltage when accelerator pedal fully depressed is approximately 4V.




WIRING DIAGRAM




DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION
1. Start engine and warm it up sufficiently.
2. Turn ignition switch "OFF".
3. Disconnect throttle position sensor harness connector.




4. Make sure that resistance between terminals (2) and (3) changes when opening throttle valve manually.




If NG, replace throttle position sensor.