Posted in MMC L200

P1299 – Variable Geometry Turbocharger Control System Malfunction (low pressure) Vehicles withvariable geometry turbocharger MMC L200 IV

 Posted by  Posted on September 29, 2020

FUNCTION

  • The engine-ECU controls the duty ratio of the variable geometry control solenoid valve so that the actual boost pressure can become the target boost pressure.

    • TROUBLE JUDGEMENT

  • Engine is running
  • Actual boost pressure is lower than target boost pressure by less than 6.7 kPa

    • PROBABLE CAUSES

  • Failed variable geometry turbocharger control system
  • Failed engine-ECU

    • DIAGNOSTIC PROCEDURE

    STEP 1. Check on intercooler air hose.

  • Check whether the hose between turbocharger and inlet manifold is disconnected or damaged.

    • Q. Is the check result normal?

    STEP 2. Check on vacuum hose of manifold absolute pressure sensor.

  • Check whether the vacuum hose of manifold absolute pressure sensor is disconnected or damaged.

    • Q. Is the check result normal?

    STEP 3. Check turbocharger supercharging pressure..

    Q. Is the check result normal?

    STEP 4. Check on clogged intercooler.

  • Check whether the intercooler is being clogged or not.

    • Q. Is the check result normal?

    STEP 5. Check on clogged EGR cooler.

  • Check whether the EGR cooler is being clogged or not.

    • Q. Is the check result normal?

    STEP 6. Check on clogged EGR pipe (A, B).

  • Check whether the EGR pipe (A, B) is being clogged or not.

    • Q. Is the check result normal?

    STEP 7. M.U.T.-III diagnosis code

  • Reconfirmation of diagnosis code.

    • Q. Is the check result normal?

    Author: admin