DTC    P0234    Turbocharger / Supercharger Overboost Condition
DTC    P0299    Turbocharger / Supercharger Underboost

for Preparation Click here

DESCRIPTION

HINT:

1. If DTC P0234 or P0299 is stored, the following symptoms may appear.
   
1. Poor acceleration
   

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

When replacing the ECM, the ECM needs Registration and Initialization (Click here).

HINT:

1. When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the intelligent tester. Then after installing the new ECM, perform all of the initializations/registrations for the "Learning Values Write" function by following the instructions shown on the tester display.
   
2. Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.
   

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch to ON and turn the tester on.
   

3. Enter the following menus: Powertrain / Engine and ECT / DTC.
   

4. Read the DTCs.
   

   Result 

   Result	Proceed to
   DTC P0234 or P0299	A
   DTC P0234 or P0299 and other DTCs	B

   HINT:

   If any DTCs other than P0234 or P0299 are output, troubleshoot those DTCs first.

B	GO TO DTC CHART (Click here)

A

1. Connect the intelligent tester to the DLC3.
   

2. Start the engine and turn the tester on.
   

3. Enter the following menus: Powertrain / Engine and ECT / Data List / MAP and Target Booster Pressure.
   

4. Take a snapshot when then engine is idling and the engine speed is maintained at 4500 rpm with no load.
   

5. Check the condition of the vehicle using the snapshot.
   
   

   Result 

   Result	Proceed to
   Difference between MAP and Target Booster Pressure is +/- 15 kPa or more	A
   Except above	B

B	Go to step 6

A

1. Check for air leaks and blockages between the air cleaner case and the turbocharger, and between the turbocharger and the intake manifold.
   

   Result 

   Result	Proceed to
   Leaks and/or blockages exists in the intake system	A
   No leaks and/or blockages in the intake system	B

   HINT:

   1. Inspect air intake system, especially hoses and pipes between the air cleaner and the turbocharger.
      
   2. Check for abnormal disconnection, pipe and hose squashing, and any damages in the intake system.
      
   3. Using your hand, check whether the pipes and hoses in the intake system are securely connected.
      
   4. By applying soapy water and revving up the engine, air leaks from the intake system can be checked by checking for bubbles.
      
   5. Check for any modifications in the intake system made by the user.
      

B	Go to step 5

A

1. Repair or replace the malfunctioning parts of the intake system.
   

NEXT	Go to step 6

1. Check the motor movement when turning the ignition switch to ON, when starting the engine, and then when turning the ignition switch off.
   

   OK:

   Motor moves smoothly as shown in the illustration.
   

OK	Go to step 9
NG	Go to step 7

1. Connect the intelligent tester to the DLC3.
   

2. Clear the DTCs (Click here).
   

3. Turn the ignition switch off.
   

4. Start the engine and warm it up until the engine coolant temperature sensor reaches 75°C (167°F) or more.
   

5. Drive the vehicle at steady speed driving with a high engine load (at an engine speed of 3000 rpm or more).
   

   HINT:

   Altitude should be below 1000 m from sea level.

6. Enter the following menus: Powertrain / Engine and ECT / DTC.
   

7. Read the DTCs.
   

   Result 

   Result	Proceed to
   No DTC output	A
   DTC P0234 or P0299	B

B	Go to step 7

A
CHECK FOR INTERMITTENT PROBLEMS (Click here)

1. Disconnect the DC motor connector.
   

2. Measure the resistance according to the value(s) in the table below.
   

   Standard Resistance:

   Tester Connection	Condition	Specified Condition
   1 (M-) - 2 (M+)	Always	0.3 to 100 Ω

   Text in Illustration 

   *1	Component without harness connected (DC Motor)

3. Reconnect the DC motor connector.
   

NG	Go to step 18

OK

1. Disconnect the DC motor connector.
   

2. Disconnect the ECM connector.
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard Resistance (Check for Open):

   Tester Connection	Condition	Specified Condition
   B40-2 (M+) - B9-34 (M+)	Always	Below 1 Ω
   B40-1 (M-) - B9-33 (M-)	Always	Below 1 Ω

   Standard Resistance (Check for Short):

   Tester Connection	Condition	Specified Condition
   B40-2 (M+) or B9-34 (M+) - Body ground	Always	10 kΩ or higher
   B40-1 (M-) or B9-33 (M-) - Body ground	Always	10 kΩ or higher

   Text in Illustration 

   *1	Front view of wire harness connector (to DC Motor)
   *2	Front view of wire harness connector (to ECM)

4. Reconnect the DC motor connector.
   

5. Reconnect the ECM connector.
   

NG	Go to step 22

OK

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch to ON and turn the tester on.
   

3. Enter the following menus: Powertrain / Engine and ECT / Data List / MAP and Atmosphere Pressure.
   

4. Compare the values when the ignition switch is ON.
   

   Standard:

   Difference between the MAP and the Atmosphere Pressure is less than 7 kPa.
   

   HINT:

   Standard atmospheric pressure is 101 kPa. For every 100 m increase in altitude, pressure drops by 1 kPa. Varies by weather.

OK	Go to step 11
NG	Go to step 10

1. Disconnect the turbo pressure sensor connector.
   

2. Disconnect the ECM connector.
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard Resistance (Check for Open):

   Tester Connection	Condition	Specified Condition
   A34-2 - A19-13 (PIM)	Always	Below 1 Ω
   A34-3 - A19-14 (VPIM)	Always	Below 1 Ω
   A34-1 - A19-15 (EPIM)	Always	Below 1 Ω

   Standard Resistance (Check for Short):

   Tester Connection	Condition	Specified Condition
   A34-2 or A19-13 (PIM) - Body ground	Always	10 kΩ or higher
   A34-3 or A19-14 (VPIM) - Body ground	Always	10 kΩ or higher
   A34-1 or A19-15 (EPIM) - Body ground	Always	10 kΩ or higher

   Text in Illustration 

   *1	Front view of wire harness connector (to Turbo Pressure Sensor)
   *2	Front view of wire harness connector (to ECM)

4. Reconnect the turbo pressure sensor connector.
   

5. Reconnect the ECM connector.
   

OK	Go to step 19
NG	Go to step 22

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch to ON and turn the tester on.
   

3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Diesel Throttle Target Angle.
   

4. When changing the Active Test value from 0 to 90%, check that Actual Throttle Position smoothly changes to the set opening angle.
   

   Standard Value:

   Value smoothly changes to the set opening angle.
   

OK	Go to step 13
NG	Go to step 12

1. Disconnect the diesel throttle body assembly connector.
   

2. Disconnect the ECM connector.
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard Resistance (Check for Open):

   Tester Connection	Condition	Specified Condition
   A19-43 (M+) - B37-2 (M+)	Always	Below 1 Ω
   A19-42 (M-) - B37-1 (M-)	Always	Below 1 Ω

   Standard Resistance (Check for Short):

   Tester Connection	Condition	Specified Condition
   A19-43 (M+) or B37-2 (M+) - Body ground	Always	10 kΩ or higher
   A19-42 (M-) or B37-1 (M-) - Body ground	Always	10 kΩ or higher

   Text in Illustration 

   *1	Front view of wire harness connector (to Diesel Throttle Body Assembly)
   *2	Front view of wire harness connector (to ECM)

4. Reconnect the diesel throttle body assembly connector.
   

5. Reconnect the ECM connector.
   

OK	Go to step 21
NG	Go to step 22

1. Connect the intelligent tester to the DLC3.
   

2. Turn the ignition switch to ON and turn the tester on.
   

3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position.
   

4. When changing the Active Test value from 0 to 100%, check that Actual EGR Valve Pos. smoothly changes to the set opening angle.
   

   Standard Value:

   Value smoothly changes to the set opening angle.
   

OK	Go to step 15
NG	Go to step 14

1. Disconnect the electric EGR valve assembly connector.
   

2. Disconnect the ECM connector.
   

3. Measure the resistance according to the value(s) in the table below.
   

   Standard Resistance (Check for Open):

   Tester Connection	Condition	Specified Condition
   B9-23 (EGM+) - B50-1 (M+)	Always	Below 1 Ω
   B9-22 (EGM-) - B50-2 (M-)	Always	Below 1 Ω

   Standard Resistance (Check for Short):

   Tester Connection	Condition	Specified Condition
   B9-23 (EGM+) or B50-1 (M+) - Body ground	Always	10 kΩ or higher
   B9-22 (EGM-) or B50-2 (M-) - Body ground	Always	10 kΩ or higher

   Text in Illustration 

   *1	Front view of wire harness connector (to Electric EGR Valve Assembly)
   *2	Front view of wire harness connector (to ECM)

4. Reconnect the electric EGR valve assembly connector.
   

5. Reconnect the ECM connector.
   

NG	Go to step 22

OK

1. Remove the electric EGR valve assembly.
   

2. Check that the EGR valve is fully closed.
   

   OK:

   The EGR valve fully closes.
   

   
   
   
   

   NOTICE:

   When cleaning the electric EGR control valve, use a piece of cloth. Spraying the solvent directly onto these parts or soaking the parts in the solvent may damage the parts.

   HINT:

   1. Hold the EGR valve to a light and confirm that the valve contacts with the valve seat securely.
      
   2. If light leaks out from the valve, the EGR valve is not fully closed.
      
   3. If the EGR valve cannot close fully, hesitation or poor acceleration almost certainly has occurred while driving the vehicle.
      
   4. Even if the EGR valve is closed completely, light leaks from the closed gap of valve seat (A part) as shown the in the illustration, but this is normal.
      

NG	Go to step 20

OK

1. Check the deposit in the EGR passage.
   

   
   
   
   

   OK:

   No deposit.
   

NG	Go to step 23

OK

1. Check for exhaust gas leak.
   

   OK:

   No exhaust gas leak.
   

OK	Go to step 25
NG	Go to step 24

1. Replace the turbocharger sub-assembly (Click here).
   

2. Turn the ignition switch to ON.
   

3. Turn the ignition switch off and wait for 30 seconds of more.
   

NEXT	Go to step 25

1. Replace the turbo pressure sensor (Click here).
   

NEXT	Go to step 25

1. Replace the electric EGR valve assembly (Click here).
   

2. Turn the ignition switch to ON.
   

3. Turn the ignition switch off and wait for 30 seconds of more.
   

NEXT	Go to step 25

1. Replace the diesel throttle body assembly (Click here).
   

2. Turn the ignition switch to ON.
   

3. Turn the ignition switch off and wait for 30 seconds of more.
   

NEXT	Go to step 25

NEXT	Go to step 25

1. Remove the electric EGR valve assembly, diesel throttle body assembly, intake air connector, EGR pipe connector, EGR w/cooler pipe assembly and EGR valve assembly No. 2.
   

2. Remove the deposits from those parts and clean them.
   

   NOTICE:

   1. When cleaning the EGR valve and the diesel throttle body, use a piece of cloth. Spraying the solvent directly onto these parts or soaking the parts in the solvent may damage the parts.
      
   2. Extreme care must be taken to prevent the removed deposits from falling into the engine unit during cleaning.
      

   HINT:

   1. Remove the intake manifold from the cylinder head when it has to be cleaned.
      
   2. Do not leave any deposits in the EGR valve assembly when cleaning the valve.
      

3. Reinstall the electric EGR valve assembly, diesel throttle body assembly, intake air connector, EGR pipe connector, EGR w/cooler pipe assembly and the EGR valve assembly No. 2.
   

NEXT	Go to step 25

NEXT

1. Connect the intelligent tester to the DLC3.
   

2. Clear the DTCs (Click here).
   

3. Turn the ignition switch off and wait for 30 seconds.
   

4. Start the engine and warm it up until the engine coolant temperature sensor reaches 75°C (167°F) or more. (A)
   

5. Drive the vehicle at steady speed driving with a high engine load (at an engine speed of 3000 rpm or more). (B)
   

   HINT:

   Altitude should be below 1000 m from sea level.

6. Enter the following menus: Powertrain / Engine and ECT / DTC.
   

7. Read the DTCs.
   

   HINT:

   Perform the following procedure using the tester to determine whether or not the DTC judgment has been carried out.

   1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
      

   2. Input DTC P0234 or P0299.
      

   3. Check that STATUS is NORMAL. If STATUS is INCOMPLETE or UNKNOWN, repeat the (A) and (B) driving pattern process.
      

      Result 

      Result	Proceed to
      ABNORMAL	A
      NORMAL	B

B	END

A

1. Replace the ECM (Click here).
   

NEXT

1. Connect the intelligent tester to the DLC3.
   

2. Clear the DTCs (Click here).
   

3. Turn the ignition switch off and wait for 30 seconds.
   

4. Start the engine and warm it up until the engine coolant temperature sensor reaches 75°C (167°F) or more. (A)
   

5. Drive the vehicle at steady speed driving with a high engine load (at an engine speed of 3000 rpm or more). (B)
   

   HINT:

   Altitude should be below 1000 m from sea level.

6. Enter the following menus: Powertrain / Engine and ECT / DTC.
   

7. Confirm that the DTC is not output again.
   

   HINT:

   Perform the following procedure using the tester to determine whether or not the DTC judgment has been carried out.

   1. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
      

   2. Input DTC P0234 or P0299.
      

   3. Check that STATUS is NORMAL. If STATUS is INCOMPLETE or UNKNOWN, repeat the (A) and (B) driving pattern process.
      

NEXT
END