Code No. P1299: Variable Geometry Turbocharger Control System Malfunction (low pressure)




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 JUDGMENT


Check Condition
  • Engine is running
Judgment Criterion
  • 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 the turbocharger supercharging pressure.



  • Check the turbocharger supercharging pressure (refer to GROUP 15 - On-vehicle Service - Turbocharger Supercharging Pressure Check <4M4> ).

Q. Is the check result normal?

Go to Step 2 .
Repair the variable geometry turbocharger control system.

STEP 2. M.U.T.-III diagnosis code.



  • After clearing the diagnosis code through M.U.T.-III, start the engine and confirm whether the diagnosis code is output.

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 ). After registering the injector identification code, the vehicle equipped with the closed type DPF carries out the forcible DPF regeneration. (Refer to GROUP 17 - Diesel Particulate Filter (DPF) System - Forcible DPF Regeneration ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).