P0089 – Suction Control Valve Stuck MMC L200 IV

OPERATION

Battery power is supplied from the engine-ECU (terminal No. 131) to the suction control valve (terminal No. 1).

The engine-ECU (terminal No. 146) turns on the power transistor to flow current to the suction control valve (terminal No. 2).

FUNCTION

The engine-ECU monitors the signals input from the rail pressure sensor.

The engine-ECU monitors the difference between the target fuel pressure and actual fuel pressure to check whether the suction control valve is open or fixed.

TROUBLE JUDGMENT

Battery positive voltage is 8 – 16 V

2 seconds later after the ignition switch has been in “ON” position or the engine has started up

The actual rail pressure remains higher than the objective rail pressure by 10 MPa or more for a certain interval.

PROBABLE CAUSES

Failed suction control valve

Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test.

Item 19: Suction control valve

Q. Is the check result normal?

STEP 2. Make a check on the following items.

Check for foreign matters (water, kerosene, etc.) in fuel and replace if necessary.

Check fuel filter itself.

Q. Are the check results normal?

STEP 3. M.U.T.-III diagnosis code.

Reconfirmation of diagnosis code

Q. Is the diagnosis code set?

STEP 4. Replace the suction control valve.

After learning the supply pump assembly, re-check the trouble symptoms