Inspection Procedure 28: Throttle Valve Control Motor System










OPERATION



  • The electric current from the engine-ECU (terminal No. 142 and No. 131) to the electronic-controlled throttle valve (terminal No. 1 and No. 2) is controlled.

FUNCTION



  • Engine-ECU changes current direction according to the Open/Close direction and also changes current to the motor coil in order to the control throttle valve control motor.

PROBABLE CAUSES



  • Failed throttle valve control motor.
  • Open/short circuit or harness damage in throttle valve control motor circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE


STEP 1. Connector check: B-20 electronic-controlled throttle valve connector


Q. Is the check result normal?

Go to Step 2 .
Repair or replace the connector.

STEP 2. Connector check: B-16 engine-ECU connector


Q. Is the check result normal?

Go to Step 3 .
Repair or replace the connector.

STEP 3. Check harness between B-16 (terminal No. 142) engine-ECU connector and B-20 (terminal No. 1) electronic-controlled throttle valve connector.



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

Q. Is the check result normal?

Go to Step 4 .
Repair the damaged harness wire.

STEP 4. Check harness between B-16 (terminal No. 131) engine-ECU connector and B-20 (terminal No. 2) electronic-controlled throttle valve connector.



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

Q. Is the check result normal?

Go to Step 5 .
Repair the damaged harness wire.

STEP 5. Replace the electronic-controlled throttle valve assembly.



  • After replace the electronic-controlled throttle valve assembly, re-check the trouble symptoms.

Q. Does trouble symptom persist?

Repair the engine-ECU.
The check is end.