Code No. P1276: Fuel Filter Exchange <Vehicles without swirl control valve>








OPERATION



  • The battery voltage is applied to the fuel filter pressure switch (terminal No. 1) from the engine-ECU (terminal No. 110)

FUNCTION



  • The engine-ECU detects the clogged fuel filter by using the fuel filter pressure switch installed on the fuel filter assembly.

TROUBLE JUDGMENT


Check Condition
  • During steady driving after engine warm up.
Judgment Criterion
  • Determination of clogged fuel filter.

PROBABLE CAUSES



  • Failed fuel filter pressure switch
  • Open circuit or harness damage in fuel filter pressure switch circuit or loose connector contact.
  • Clogged fuel filter
  • Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-133 fuel filter pressure switch connector

Q. Is the check result normal?
Go to Step 2 .
Repair or replace the connector.

STEP 2. Perform voltage measurement at B-133 fuel filter pressure switch connector.

  • Disconnect connector, and measure at harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 1 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 6 .
Go to Step 3 .

STEP 3. Connector check: D-215 engine-ECU connector

Q. Is the check result normal?
Go to Step 4 .
Repair or replace the connector.

STEP 4. Check harness between D-215 (terminal No. 110) engine-ECU connector and B-133 (terminal No. 1) fuel filter pressure switch connector.

  • Check output line for open/short circuit.

Q. Is the check result normal?
Go to Step 5 .
Repair the damaged harness wire.

STEP 5. M.U.T.-III data list.

  • Refer to Data List Reference Table .

  1. Item 152: Fuel filter pressure switch

Q. Is the diagnosis code set?
Replace the engine-ECU. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - Precautions Before Service - How to Perform Chassis Number Writing ). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 6. Perform resistance measurement at B-133 fuel filter pressure switch connector.

  • Disconnect connector, and measure at harness side.
  • Resistance between terminal No. 2 and earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?
Go to Step 7 .

    Check and repair harness between B-133 (terminal No. 2) fuel filter pressure switch connector and body earth.

    • Check earthing line for open circuit and damage.

STEP 7. Connector check: D-215 engine-ECU connector

Q. Is the check result normal?
Go to Step 8 .
Repair or replace the connector.

STEP 8. Check harness between D-215 (terminal No. 110) engine-ECU connector and B-133 (terminal No. 1) fuel filter pressure switch connector.

  • Check output line for damage.

Q. Is the check result normal?
Go to Step 9 .
Repair the damaged harness wire.

STEP 9. Replace the Fuel filter cartridge.

  • After replacing the Fuel filter cartridge, reconfirm whether the diagnosis code is set.

Q. Is the diagnosis code set?
Replace the Fuel filter pump.
Check end.