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Circuit/System Testing

WARNING: This page is about a different car, the 2018 Buick Envision. However, it is still accessible from the selected car via links, so may be relevant.
  1. Vehicle OFF/Ignition OFF.
  2. Verify the LVDS interface cable is properly connected at the K48 Infotainment Faceplate Control Module and the K74 Human Machine Interface Control Module connections and there is no damage to the cable or connections.
  3. Ignition ON/Vehicle in Service Mode, infotainment system ON.
  4. Verify the K48 Infotainment Faceplate Control Module does not display an image.
    • If the K48 Infotainment Faceplate Control Module displays an image. 

      All OK.

    • Go to next step: If the K48 Infotainment Faceplate Control Module does not display an image. 
  5. Vehicle OFF/Ignition OFF.
  6. Disconnect the LVDS interface cable from the K48 Infotainment Faceplate Control Module.
  7. Connect the EL-50334-2 Type A female to Mini B male USB Cable to the K48 Infotainment Faceplate Control Module. Connect the EL-50334-14 Infotainment Test Cable to the adapter.
  8. Disconnect the LVDS interface cable from the K74 Human Machine Interface Control Module. Connect the EL-50334 - 14 Infotainment Test cable to the K74 Human Machine Interface Module.
  9. Ignition ON/Vehicle in Service Mode, infotainment system ON.
  10. Verify the K48 Infotainment Faceplate Control Module displays an image.
    • If the K48 Infotainment Faceplate Control Module does not display an image 
    1. Replace the K48 Infotainment Faceplate Control Module. Connect all harness connectors.
    2. Ignition ON/Vehicle in Service Mode, infotainment system ON.
    3. Verify the K48 Infotainment Faceplate Control Module displays an image.
      • If the K48 Infotainment Faceplate Control Module still does not display an image, replace the K74 Human Machine Interface Control Module.
      • Go to next step: If the K48 Infotainment Faceplate Control Module displays an image.
    4. All OK.
    • Go to next step: If the K48 Infotainment Faceplate Control Module displays an image. 
  11. Replace the vehicle LVDS interface cable from the K48 Infotainment Faceplate Control Module to the K74 Human Machine Interface Module.
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