GSIC - Global Service Information Center

### DTC P0234/34 Turbocharger / Supercharger Overboost Condition

### DTC P0299/34 Turbocharger / Supercharger Underboost

### DTC P1251/34 Step Motor for Turbocharger Control Circuit (Intermittent)

## for Preparation Click here

## DESCRIPTION

HINT:

  *: Only for 1KD-FTV

Refer to DTC P0045/34 on page Click here.

DTC No. | DTC Detection Condition | Trouble Area

P0234/34

When turbocharger boost pressure continues to be higher than ECM's target boost pressure.
(1 trip detection logic)

1. Turbocharger sub-assembly
2. Turbo motor driver
3. Manifold absolute pressure sensor
4. MAF meter
5. EGR valve stuck closed
6. Exhaust system and intake system are modified or clogged
7. ECM

P0299/34

When turbocharger boost pressure continues to be lower than ECM's target boost pressure.
(1 trip detection logic)

1. Turbocharger sub-assembly
2. Turbo motor driver
3. Manifold absolute pressure sensor
4. MAF meter
5. EGR valve stuck open
6. Manifold absolute pressure sensor (hose disconnected)
7. Exhaust system and intake system are modified or clogged
8. ECM

P1251/34

When turbocharger boost pressure is higher than boost pressure for a short time in which there was possibility of engine damage.
(1 trip detection logic)

1. Turbocharger sub-assembly
2. Turbo motor driver
3. Manifold absolute pressure sensor
4. MAF meter
5. EGR valve assembly
6. Exhaust system and intake system are modified or clogged
7. ECM

## WIRING DIAGRAM

Refer to DTC P0045/34 on page Click here.

## INSPECTION PROCEDURE

HINT:

  Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, and other data from the time the malfunction occurred.

NOTICE:

  If the ECM is replaced, the new ECM needs initialization (Click here).

1.CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0234/34, P0299/34 AND /OR P1251/34)

1. Connect the intelligent tester to the DLC3.

1. Turn the ignition switch ON and turn the intelligent tester ON.

1. Enter the following menus: Powertrain / Engine / DTC.

1. Read the DTCs.

   Result:

     Display (DTC Output) | Proceed to
     P0234/34, P0299/34 and/or P1251/34 | A
     P0234/34, P0299/34 and/or P1251/34 and other DTCs | B

| B |

GO TO RELEVANT DTC CHART

A |

2.READ DATA LIST (MAP)

1. Connect the intelligent tester to the DLC3.

1. Start the engine and warm it up. Turn the intelligent tester ON.

1. Enter the following menu: Powertrain / Engine / Data List / MAP.

   Standard:

     Item | Engine Speed* | Reference Value
     MAP | Ignition switch ON | Same as atmospheric pressure
     MAP | Idling | 95 to 105 kPa (713 to 788 mmHg, 28.1 to 31 in.Hg)
     MAP | 3,000 rpm (no engine load) | 110 to 135 kPa (825 to 1,012 mm Hg, 32.5 to 39.9 in.Hg)

   HINT:
     *: If no idling conditions are specified, the A/C switch and all accessory switches should be OFF with a fully warm engine.

| NG |

REPLACE MANIFOLD ABSOLUTE PRESSURE SENSOR

OK |

3.CHECK EXHAUST SYSTEM

1. Turn the ignition switch ON.

1. Check the exhaust pipe for leaks.

   OK:
     Exhaust pipe has no leaks.

| NG |

REPAIR OR REPLACE

OK |

4.CHECK AIR CLEANER FILTER

1. Check that the air cleaner filter is not clogged.

   OK:
     Air cleaner filter is not clogged.

| NG |

REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSY

OK |

5.CHECK INTAKE SYSTEM

1. Disconnect the air cleaner hose.

1. Use a mirror to visually check the turbocharger for any mechanical problems.

1. When the engine is cold, check that the impeller of the turbocharger rotates smoothly, and perform a contact check to confirm whether there is any damage on it.

   OK:
     impeller of turbocharger rotates smoothly.

| NG |

REPAIR OR REPLACE INTAKE SYSTEM

OK |

6.INSPECT TURBOCHARGER SUB-ASSEMBLY

1. Disconnect the air cleaner hose.

1. Use a mirror to visually check the turbocharger for any mechanical problems.

1. When the engine is cold, check that the impeller of the turbocharger rotates smoothly, and perform a contact check to confirm whether there is any damage on it.

   OK:
     Impeller of turbocharger rotates smoothly.

| NG |

REPLACE TURBOCHARGER SUB-ASSEMBLY

OK |

7.CHECK ECM (VNTI VOLTAGE)

1. While idling the engine, check the waveform of the ECM connectors using an oscilloscope.

   Standard voltage:

     Tester Connection | Specified Condition
     E8-17 (VNTI) - E7-7 (E1) | Correct waveform is shown

| NG |

REPLACE ECM

OK |

8.CHECK ECM (VNTO VOLTAGE)

1. While idling the engine, check the waveform of the ECM connectors using an oscilloscope.

   Standard voltage:

     Tester Connection | Specified Condition
     E8-10 (VNTO) - E7-7 (E1) | Correct waveform is shown

| NG |

REPLACE TURBO MOTOR DRIVER

OK |

9.CHECK EGR VALVE ASSEMBLY

| NG |

REPLACE EGR VALVE ASSEMBLY

OK |

10.INSPECT INTAKE AIR TEMPERATURE SENSOR

1. Check the IAT sensor.

   1. Remove the MAF meter.

   2. Measure the resistance of the sensor.

      Standard resistance:

        Tester Connection | Condition | Specified Condition
        4 - 5 | -20°C (-4°F) | 13.6 to 18.4 kΩ
        4 - 5 | 20°C (68°F) | 2.21 to 2.69 kΩ
        4 - 5 | 60°C (140°F) | 0.49 to 0.67 kΩ

| NG |

REPLACE MASS AIR FLOW METER

OK |

REPLACE ECM