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Home >> Buick >> 2020 >> Envision Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 154 (Battery, Charging System And Starting System) >> Diagnostic Information and Procedures >> DTC P0621 >> Circuit/System Verification
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Circuit/System Verification

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2020 Buick Regal TourX, 2020 Buick Regal, 2019 Buick Regal TourX, 2019 Buick Regal, and 2018 Buick Regal TourX. However, it is still accessible from the selected car via links, so may be relevant.
  1. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
  2. Verify the DTC does not set.
    • If the DTC sets 

      Refer to Circuit/System Testing.

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