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Home >> Buick >> 2016 >> Envision >> Repair and Diagnosis >> External Pages >> Different car >> Section 180 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> DTC B1446 or B1447: Backup Power Source >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page is about a different car, the 2016 Buick LaCrosse. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF/Vehicle OFF and all vehicle systems OFF, disconnect the X1 harness connector at the K73 Telematics Communication Interface Control Module. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for greater than 12.3 V between the B+ circuit terminal 14 and the low reference circuit terminal 13.
    • If 12.3 V or less 

      Test or replace the C3 Telematics Communication Interface Control Module Battery.

    • If greater than 12.3 V 
  3. Replace the K73 Telematics Communication Interface Control Module.