Throttle Body: Testing and Inspection
1. REMOVE V-BANK COVER2. INSPECT SYSTEM OPERATION
a. Check that the throttle linkage moves smoothly.
b. Inspect the throttle control motor for operating sound.
1. Turn the ignition switch ON.
2. When turning the accelerator pedal position sensor lever, check the running sound of the motor. Also, check that there is no friction sound.
If operation is not as specified, check the throttle control motor (See step 4), wiring and ECM.
c. Inspect the accelerator pedal position sensor
1. Connect the LEXUS hand-held tester to the DLC3.
2. Check that the MIL does not light up.
3. When turning the accelerator pedal position sensor lever to the full-open position, check that the throttle valve opening percentage (THROTTLE POS) of the CURRENT DATA shows the standard value.
Standard throttle valve opening percentage:
60 % or more
If operation is not as specified, check that the accelerator pedal position sensor (See step 5), wiring and ECM.
If you have no LEXUS hand-held tester, measure voltage between terminals VPA and E2 of the ECM connector.
d. Inspect the air assist system.
1. Start the engine and check that the MIL does not light up.
2. Allow the engine to warm up to normal operating temperature.
3. Turn the AC conditioning ON to OFF, and check the idle speed.
Idle speed (Transmission in neutral): 750 ± 50 rpm
NOTE: Perform inspection under condition without electrical load.
e. After checking the above (b) to (d), perform the driving test and check that there is no sense of incongruity.
3. INSPECT THROTTLE CONTROL MOTOR W/ CLUTCH
a. Disconnect the throttle control motor w/ clutch connector.
b. Using an ohmmeter, measure the motor resistance between terminal 1 (M+) and 2 (M-).
Motor resistance: 0.3 - 100 Ohms at 20 °C (68 °F)
If the resistance is not as specified, replace the throttle control motor W/ clutch.
c. Using an ohmmeter, measure the clutch resistance between terminal 3 (CL-) and 4 (CL+).
Clutch resistance: 4.2 - 5.2 Ohms at 20 °C (68 °F)
If the resistance is not as specified, replace the throttle control motor W/ clutch.
d. Reconnect the throttle control motor connector.
4. INSPECT THROTTLE POSITION SENSOR
a. Disconnect the throttle position sensor connector.
b. Using an ohmmeter, measure the resistance between terminals VC and E2.
Resistance: 1.25 - 2.35 kOhms at 20 °C (68 °F)
If the resistance is not as specified, replace the throttle position sensor.
c. Reconnect the throttle position sensor connector.
5. INSPECT ACCELERATOR PEDAL POSITION SENSOR
a. Disconnect the accelerator position sensor connector.
b. Using an ohmmeter, measure the resistance between terminals VC and E2.
Resistance: 1.64 - 3.28 Ohms at 20 °C (68 °F)
If the resistance is not as specified, replace the accelerator pedal position sensor.
c. Reconnect the accelerator pedal position sensor connector.
6. REINSTALL V-BANK COVER