P0234-BOOST PRESSURE SENSOR NEGATIVE DEVIATION





For a complete wiring diagram Refer to Section 8W


  • When Monitored:

    With the engine running.

  • Set Condition:

    The Boost Pressure Sensor indicates actual turbocharger boost is less than the ECM setpoint.


Possible Causes
  
AIR FILTER
  
AIR RESTRICTION
  
AIR LEAKS
  
BOOST CONTROL VACUUM SUPPLY
  
BOOST PRESSURE ACTUATOR
  
TURBOCHARGER
  



Diagnostic Test

1.CHECK FOR ACTIVE DTC

NOTE: If the ECM detects and stores a DTC, the ECM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the scan tool at the same time the DTC is displayed.


NOTE: Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC.


NOTE: Ensure all turbocharger inlet and outlet tubes are connected properly, without damage and restriction before continuing with this test.


NOTE: If DTC P0401 or P0402 is present with this DTC, diagnose P0401 or P0402 before diagnosing this DTC.






NOTE: A clogged Boost Pressure Solenoid Air Filter can cause this DTC to set. Inspect this filter and replace as necessary before continuing with this test.



Did this DTC set again?

Yes
  • Go To2


No
  • Test Complete.

2.AIR FILTER




Were any of these problems found?

Yes


No
  • Go To3

3.AIR RESTRICTION

NOTE: Inspect all air intake and turbocharger related tubes for damage, restriction or poor connection. Any of these conditions can cause a this DTC to set.




Were any problems found?

Yes


No
  • Go To4

4.CHECKING THE BOOST CONTROL VACUUM SUPPLY



Were any problems found?

Yes


No
  • Go To5

5.CHECKING FOR AIR LEAKS





Is there evidence of smoke leakage?

Yes


No
  • Go To6

6.BOOST PRESSURE ACTUATOR


NOTE: Ensure the ECM and Boost Pressure Actuator harness connectors are connected.





Did this DTC set again?

Yes


No