LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 2018 >> Regal Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Infotainment >> Cellular System, Entertainment System, And Navigation System - Diagnostic Information And Procedures >> Diagnostic Information and Procedures >> DTC B1024 (Human Machine Interface Control Module) >> Circuit/System Verification
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Verification

NOTE:

Allow the vehicle cabin to cool if the temperature inside the vehicle is excessive before proceeding with this diagnostic procedure.

  1. Verify the DTC sets outside of the Conditions for Running and Setting. Since most occurrences of this DTC are caused by extreme vehicle cabin temperatures due to ambient conditions, review with the customer the conditions under which the DTC set.
    • If the DTC sets within the Conditions for Running and Setting. 

      The system is operating as designed, All OK.

    • Go to next step: If the DTC sets outside the Conditions for Running and Setting. 
  2. Using the scan tool, clear the DTC.
  3. Verify the DTC does not set while operating the infotainment system under the conditions the customer experienced the concern.
    • If the DTC sets 

      Replace the K74 Human Machine Interface Control Module

    • Go to next step: If the DTC does not set 
  4. All OK.