Inspection Procedure 17: No. 4 Injector System








OPERATION



  • Power is supplied to the No. 4 injector (terminal No. 1) from the engine-ECU (terminal No. 112).
  • The power voltage is earthed to the engine-ECU (terminal No. 136) from the No. 4 injector (terminal No. 2).

FUNCTION



  • The engine-ECU controls the power supply interval of the No. 4 injector.
  • The fuel injection amount of the No. 4 injector depends on the power supply interval.

PROBABLE CAUSES



  • Failed No. 4 injector
  • Open/short circuit or harness damage in injector circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-106 No. 4 injector 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-106 (terminal No. 1) No. 4 injector connector and B-16 (terminal No. 112) engine-ECU connector.

  • Check power supply 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-106 (terminal No. 2) No. 4 injector connector and B-16 (terminal No. 136) engine-ECU connector.

  • Check earthing 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 No. 4 injector.



  • After replacing the No. 4 injector, re-check the trouble symptoms.

Q. Does trouble symptom persist?
Replace the engine-ECU.
The check is end.