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Circuit/System Testing

Driver Outside Mirror Movement Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the connector at the S79D Front Side Door Window Control Switch - Driver. It may take up to 2 minutes for all vehicle systems to power down.
  2. Verify a test lamp illuminates between ground circuit terminal 1 and B+.
    • If the test lamp does not illuminate 

      Repair the open/high resistance on circuit 2150 or ground connection.

    • Go to next step: If the test lamp illuminates 
  3. Ignition ON.
  4. Verify a test lamp illuminates between the B+ circuit terminal 8 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Test circuit 4240 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    2. Replace the X50A Engine Wiring Harness Junction Block.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Test circuit 4240 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test the following circuits for a short to ground:
      • Circuit 2788
      • Circuit 2789
      • Circuit 2790
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    3. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If the test lamp illuminates 
  5. Ignition OFF, connect the connector at the S79D Front Side Door Window Control Switch - Driver and disconnect the X1 connector at the A9A Outside Rearview Mirror-Driver. Ignition ON
  6. Connect a test lamp between the control circuit terminal 3 and control circuit terminal 10.
  7. Verify the test lamp turns ON when commanding the Up and Down states with the S79D Front Side Door Window Control Switch - Driver.
    • If the test lamp remains OFF during either of the commands 
    1. Test the following circuits for a short to ground:
      • Circuit 2788
      • Circuit 2789
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test the following circuits for an open/high resistance:
      • Circuit 2788
      • Circuit 2789
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79D Front Side Door Window Control Switch - Driver.
    • If the test lamp is always ON 
    1. Test the following circuits for a short to voltage:
      • Circuit 2788
      • Circuit 2789
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If the test lamp turns ON during each of the commands 
  8. Connect a test lamp between the control circuit terminal 10 and control circuit terminal 5.
  9. Verify the test lamp turns ON when commanding the Left and Right states with the S79D Front Side Door Window Control Switch - Driver.
    • If the test lamp remains OFF during either of the commands 
    1. Test the following circuits for a short to ground:
      • Circuit 2789
      • Circuit 2790
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test the following circuits for an open/high resistance:
      • Circuit 2789
      • Circuit 2790
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79D Front Side Door Window Control Switch - Driver.
    • If the test lamp is always ON 
    1. Test the following circuits for a short to voltage:
      • Circuit 2789
      • Circuit 2790
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If the test lamp turns ON during each of the commands 
  10. Test or replace the M77D Outside Rearview Mirror Actuator-Driver.

Driver Mirror Position Sensor Circuit Test

  1. Ignition OFF and all vehicle systems OFF, disconnect the X2 connector at the A9A Outside Rearview Mirror-Driver. It may take up to 2 minutes for all vehicle systems to power down.
  2. Verify a test lamp illuminates between the low reference circuit terminal 4 and B+.
    • If the test lamp does not illuminate 
    1. Test circuit 673 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    2. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If the test lamp illuminates 
  3. Ignition ON.
  4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 2 and ground.
    • If less than 4.8 V 
    1. Test circuit 2791 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test circuit 2791 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79D Front Side Door Window Control Switch - Driver.
    • If greater than 5.2 V 
    1. Test circuit 2791 for a short to voltage.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If between 4.8 - 5.2 V 
  5. Test for less than 4.6 V between signal circuit terminal 6 and ground.
    • If 4.6 V or greater 
    1. Test circuit 2787 for a short to voltage.
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If less than 4.6 V 
  6. Test for greater than 0.6 V between signal circuit terminal 6 and ground.
    • If 0.6 V or less 
    1. Test circuit 2787 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test circuit 2787 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If greater than 0.6 V 
  7. Test for less than 4.6 V between signal circuit terminal 1 and ground.
    • If 4.6 V or greater 
    1. Test circuit 2792 for a short to voltage.
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If less than 4.6 V 
  8. Test for greater than 0.6 V between signal circuit terminal 1 and ground.
    • If 0.6 V or less 
    1. Test circuit 2792 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test circuit 2792 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79D Front Side Door Window Control Switch - Driver.
    • Go to next step: If greater than 0.6 V 
  9. Test or replace the M77D Outside Rearview Mirror Actuator-Driver.

Passenger Outside Mirror Movement Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the connector at the S79P Front Side Door Window Switch - Passenger. It may take up to 2 minutes for all vehicle systems to power down.
  2. Verify a test lamp illuminates between ground circuit terminal 1 and B+.
    • If the test lamp does not illuminate 

      Repair the open/high resistance on circuit 2050 or ground connection.

    • Go to next step: If the test lamp illuminates 
  3. Ignition ON.
  4. Verify a test lamp illuminates between the B+ circuit terminal 8 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Test circuit 4040 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    2. Replace the X50A Engine Wiring Harness Junction Block.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Test circuit 4040 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test the following circuits for a short to ground:
      • Circuit 2796
      • Circuit 2797
      • Circuit 2798
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    3. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If the test lamp illuminates 
  5. Ignition OFF, connect the connector at the S79P Front Side Door Window Switch - Passenger and disconnect the X1 connector at the A9B Outside Rearview Mirror - Passenger. Ignition ON
  6. Connect a test lamp between the control circuit terminal 3 and control circuit terminal 10.
  7. Verify the test lamp turns ON when commanding the Up and Down states with the S79D Front Side Door Window Control Switch - Driver.
    • If the test lamp remains OFF during either of the commands 
    1. Test the following circuits for a short to ground:
      • Circuit 2796
      • Circuit 2797
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test the following circuits for an open/high resistance:
      • Circuit 2796
      • Circuit 2797
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79P Front Side Door Window Switch - Passenger.
    • If the test lamp is always ON 
    1. Test the following circuits for a short to voltage:
      • Circuit 2796
      • Circuit 2797
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If the test lamp turns ON during each of the commands 
  8. Connect a test lamp between the control circuit terminal 10 and control circuit terminal 5.
  9. Verify the test lamp turns ON when commanding the Left and Right states with the S79D Front Side Door Window Control Switch - Driver.
    • If the test lamp remains OFF during either of the commands 
    1. Test the following circuits for a short to ground:
      • Circuit 2797
      • Circuit 2798
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test the following circuits for an open/high resistance:
      • Circuit 2797
      • Circuit 2798
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79P Front Side Door Window Switch - Passenger.
    • If the test lamp is always ON 
    1. Test the following circuits for a short to voltage:
      • Circuit 2797
      • Circuit 2798
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If the test lamp turns ON during each of the commands 
  10. Test or replace the M77P Outside Rearview Mirror Actuator - Passenger.

Passenger Mirror Position Sensor Circuit Test

  1. Ignition OFF and all vehicle systems OFF, disconnect the X2 connector at the A9B Outside Rearview Mirror - Passenger. It may take up to 2 minutes for all vehicle systems to power down.
  2. Verify a test lamp illuminates between the low reference circuit terminal 4 and B+.
    • If the test lamp does not illuminate 
    1. Test circuit 675 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    2. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If the test lamp illuminates 
  3. Ignition ON.
  4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 2 and ground.
    • If less than 4.8 V 
    1. Test circuit 2799 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test circuit 2799 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79P Front Side Door Window Switch - Passenger.
    • If greater than 5.2 V 
    1. Test circuit 2799 for a short to voltage.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If between 4.8 - 5.2 V 
  5. Test for less than 4.6 V between signal circuit terminal 6 and ground.
    • If 4.6 V or greater 
    1. Test circuit 2795 for a short to voltage.
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If less than 4.6 V 
  6. Test for greater than 0.6 V between signal circuit terminal 6 and ground.
    • If 0.6 V or less 
    1. Test circuit 2795 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test circuit 2795 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If greater than 0.6 V 
  7. Test for less than 4.6 V between signal circuit terminal 1 and ground.
    • If 4.6 V or greater 
    1. Test circuit 2800 for a short to voltage.
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found.
    2. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If less than 4.6 V 
  8. Test for greater than 0.6 V between signal circuit terminal 1 and ground.
    • If 0.6 V or less 
    1. Test circuit 2800 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found.
    2. Test circuit 2800 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found.
    3. Replace the S79P Front Side Door Window Switch - Passenger.
    • Go to next step: If greater than 0.6 V 
  9. Test or replace the M77P Outside Rearview Mirror Actuator - Passenger.
  1. Vehicle ON.
  2. Verify K9 Body Control Module software is up to date.
    • If software is not up to date 

      Reprogram K9 Body Control Module.

    • Go to next step: If software is up to date 
  3. Verify reverse tilt mirror is turned on for both driver and passenger mirror through the infotainment system.
  4. Verify both driver and passenger mirrors tilt down when shifting into reverse, and return to normal when shifting out of reverse.
    • If drivers mirror doesn't tilt and return properly 

      Replace the S79D Front Side Door Window Control Switch - Driver.

    1. Replace the S79D Front Side Door Window Control Switch - Driver.
    2. Verify driver mirror tilts down when shifting into reverse, and returns to normal when shifting out of reverse.
      • If drivers mirror doesn't tilt and return properly, replace the K9 Body Control Module
      • Go to next step: If drivers mirror operates properly
    3. All OK.
    • If passenger mirror doesn't tilt and return properly 
    1. Replace the S79P Front Side Door Window Switch - Passenger.
    2. Verify passenger mirror tilts down when shifting into reverse, and returns to normal when shifting out of reverse.
      • If passenger mirror doesn't tilt and return properly, replace the K9 Body Control Module
      • Go to next step: If passenger mirror operates properly
    3. All OK.
    • If both mirrors don't tilt and return properly 

      Replace the K9 Body Control Module.

    • Go to next step: If both mirrors tilt and return properly 
  5. All OK.
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