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Home >> GMC >> 2018 >> Terrain SL >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Infotainment >> Cellular System, Entertainment System, And Navigation System - Diagnostic Information And Procedures >> Diagnostic Information And Procedures >> DTC B127E: Front Video Display Output Signal (IOB) >> Circuit/System Testing
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Circuit/System Testing

  1. Vehicle OFF/Ignition OFF, disconnect the X1 harness connector at the P17 Info Display Module
  2. Test for infinite resistance between the signal circuits listed below and ground:
    • Radio display LVDS lock signal circuit terminal 5
    • Radio display LVDS error signal circuit terminal 6
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  3. Reconnect the X1 harness connector at the P17 Info Display Module.
  4. Disconnect the LVDS interface cable from the P17 Info Display Module.
  5. Connect the EL-50334-2 Type A female to Mini B male USB Cable to the P17 Info Display Module. Connect the EL-50334-14 Infotainment Test Cable to the adapter.
  6. Disconnect the LVDS interface cable from the A11 Radio. Connect the EL-50334-14 Infotainment Test cable to the A11 Radio.
  7. Ignition ON/Vehicle in Service Mode, infotainment system ON.
  8. Verify DTC B127E is not set as current.
    • If DTC B127E is set as current 
    1. Replace the P17 Info Display Module. Connect all harness connectors.
    2. Ignition ON, infotainment system ON.
    3. Verify DTC B127E is not set as current.
      • If DTC B127E is still set as current, replace the A11 Radio.
      • If DTC B127E is not set.
    4. All OK.
    • Go to next step: If DTC B127E is not set as current. 
  9. Replace the vehicle LVDS interface cable from the P17 Info Display Module to the A11 Radio.
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