Code No. P0638: Throttle Valve Control Servo Stuck




OPERATION




FUNCTION




TROUBLE JUDGMENT


Check Conditions
Judgment Criterion

FAIL-SAFE AND BACKUP FUNCTION




PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. Check throttle valve control servo itself.



  • Throttle body assembly connector check.
  • Check throttle valve control servo itself (Refer to ).

Q. Is the check result normal?

Go to Step 2.
Repair or replace the connector, or replace the throttle body assembly.

STEP 2. Check harness between throttle body assembly connector and engine-ECU connector.



  1. Check the harness between throttle body assembly connector terminal and engine-ECU connector terminal ETV-.
  2. Check the harness between throttle body assembly connector terminal and engine-ECU connector terminal ETV+.

  • Check output line for open/short circuit and damage.

Q. Are the check results normal?

Go to Step 3.
Repair or replace the connector, or repair the damaged harness wire.

STEP 3. Replace the throttle body assembly.



  • After replace the throttle body assembly, re-check the trouble symptoms.

Q. Does trouble symptom persist?

Replace the engine-ECU.
The check is end.