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Home >> Buick >> 2017 >> Envision Base >> Repair and Diagnosis >> Body & Frame >> Mirrors >> Mirror System >> Diagnostic Information and Procedures >> Power Mirror Folding Malfunction >> Circuit/System Testing

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the appropriate A9 Outside Rearview Mirror. Ignition ON
  2. Connect a test lamp between the control circuit terminal 2 and control circuit terminal 4.
  3. Verify the test lamp turns ON when commanding the FOLD and UNFOLD states with the S52 Outside Rearview Mirror Switch.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S52 Outside Rearview Mirror Switch.
    2. Test for infinite resistance between each control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in each control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, test or replace the S52 Outside Rearview Mirror Switch.
    • If the test lamp is always ON 
    1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S52 Outside Rearview Mirror Switch, ignition ON.
    2. Test for less than 1 V between each control circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, test or replace the S52 Outside Rearview Mirror Switch
    • If the test lamp turns ON during each of the commands 
  4. Test or replace the A9 Outside Rearview Mirror.
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