The check engine light is activated, accompanied by one or more of the following fault codes related to...

Bulletin number

LI09_40-N-079144

Component

Power train

Summary

Complaint The check engine light is activated, accompanied by one or more of the following fault codes related to the Boost Pressure Positioner: • P300A6D The boost pressure is too low. Charge Air Cooler. • P300974 Component 'Boost pressure positioner' has a malfunction. The boost pressure is too low. • P300DFB Component 'Boost pressure positioner' has a malfunction. • P300DE8 Boost pressure control A has a malfunction after the cold start. Cause The potential causes for these fault codes are: A. Leak or Blockage in the Intake or Charge Air System: This can prevent the proper flow of air, affecting the boost pressure. B. Insufficient Source Vacuum, Vacuum Leak, or Sticking/Weak Vacuum Component: These issues can prevent the boost pressure positioner from functioning correctly. • For Model Year 2023-Cuurent vehicles operating at approximately 4,000 ft elevation or above, reduced ambient pressure and/or high brake demand may contribute to reduced available vacuum differential and under boost com-plaints, even when no discrete vacuum component failure is identified. C. Internal Malfunction of the Boost Pressure Positioner: The component itself may be faulty. D. Internal Defect with the Variable Turbine Geometry (VTG) System inside the Turbocharger: Issues within the turbo-charger can affect boost pressure control. Remedy Engineering Review Required: For vehicles operating at approximately 4,000 ft elevation or above, a TIPS case MUST be opened before replacing any component for fault codes P300A6D, P300974, P300DFB, or P300DE8.

Owners of these vehicles have filed 11 complaints in the transmission category.