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Home >> Buick >> 2013 >> Encore Base, AWD >> Repair and Diagnosis >> Body & Frame >> Windows >> Fixed And MOVEABLE Window System >> Diagnostic Information and Procedures >> Power Windows Malfunction (A55, A66 Without A33) >> Circuit/System Testing
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Circuit/System Testing

Driver Window Inoperative

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S79D Window Switch-Driver. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 1 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Ignition ON.
  4. Verify a test lamp illuminates between the ignition circuit terminal 3 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ignition circuit end to end.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF.
    2. Test for infinite resistance between the ignition circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for infinite resistance between the control circuits listed below and ground:
      • Control circuit terminal 4
      • Control circuit terminal 5
      • Control circuit terminal 6
      • Control circuit terminal 7
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the S79D Window Switch-Driver.
    • If the test lamp illuminates 
  5. Ignition OFF and all vehicle systems OFF, connect the harness connector at the S79D Window Switch-Driver. It may take up to 2 minutes for all vehicle systems to power down
  6. Disconnect the harness connector at the M74D Window Motor-Driver.
  7. Test for less than 10 Ω between the control circuit terminal 1 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the S79D window switch - driver.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S79D Window Switch-Driver.
    • If less than 10 Ω 
  8. Test for less than 10 Ω between the control circuit terminal 2 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the S79D Window Switch-Driver.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S79D Window Switch-Driver.
    • If less than 10 Ω 
  9. Connect a test lamp between control circuit terminal 1 and control circuit terminal 2, ignition ON.
  10. Verify the test lamp turns ON when commanding the UP and DOWN states with the S79D Window Switch-Driver.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF, disconnect the harness connector at the S79D Window Switch-Driver.
    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, replace the S79D Window Switch-Driver.
    • If the test lamp turns ON during each of the commands 
  11. Test or replace the M74D Window Motor-Driver.

Passenger Window Inoperative From Both Switches

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S79P Window Switch - Passenger. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the control circuit terminal 3 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the S79D Window Switch-Driver.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S79D Window Switch-Driver.
    • If less than 10 Ω 
  3. Test for less than 10 Ω between the control circuit terminal 6 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the S79D Window Switch-Driver.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S79D Window Switch-Driver.
    • If less than 10 Ω 
  4. Connect a test lamp between the control circuit terminal 3 and control circuit terminal 6, ignition ON.
  5. Verify the test lamp turns ON when commanding the UP and DOWN functions with the S79D Window Switch-Driver.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF, disconnect the harness connector at the S79D Window Switch-Driver.
    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, replace the S79D Window Switch-Driver.
    • If the test lamp turns ON during each of the commands 
  6. Ignition OFF and all vehicle systems OFF, connect the harness connector at the S79P Window Switch-Passenger and disconnect the harness connector at the M74P Window Motor-Passenger. It may take up to 2 minutes for all vehicle systems to power down.
  7. Test for less than 10 Ω between the control circuit terminal 1 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the S79P Window Switch-Passenger.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S79P Window Switch-Passenger.
    • If less than 10 Ω 
  8. Test for less than 10 Ω between the control circuit terminal 2 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the S79P Window Switch-Passenger.
    2. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the S79P Window Switch-Passenger.
    • If less than 10 Ω 
  9. Connect a test lamp between control circuit terminal 1 and control circuit terminal 2, ignition ON.
  10. Verify the test lamp turns ON when commanding the UP and DOWN functions with the S79P Window Switch-Passenger.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF, disconnect the harness connector at the S79P Window Switch-Passenger.
    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, replace the S79P Window Switch-Passenger.
    • If the test lamp turns ON during each of the commands 
  11. Test or replace the M74P window motor - passenger.

Passenger Window Switch Inoperative

  1. Ignition OFF, disconnect the harness connector at the S79P Window Switch-Passenger, ignition ON
  2. Verify a test lamp illuminates between the ignition circuit terminal 5 and ground.
    • If the test lamp does not illuminate 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the ignition circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is OK and there is voltage at the fuse.
    • If the test lamp illuminates 
  3. Test or replace the S79P Window Switch-Passenger.
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