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Circuit/System Testing

Outside Rearview Mirror Switch Malfunction

  1. Ignition OFF/Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the K96 Mirror Control Module. 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 14 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF/Vehicle 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.
    • Go to next step: If less than 10 Ω 
  3. Ignition ON/Vehicle in Service Mode.
  4. Verify a test lamp illuminates between the B+ circuit terminal 1 and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition OFF/Vehicle OFF.
    2. Test for less than 2 Ω in the B+ 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 not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition OFF/Vehicle OFF.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
    • Go to next step: If the test lamp illuminates 
  5. Ignition OFF/Vehicle OFF, connect the harness connector at the K96 Mirror Control Module and disconnect the harness connector at the S52 Outside Rearview Mirror Switch. It may take up to 2 minutes for all vehicle systems to power down.
  6. Test for less than 10 Ω between the low reference circuit terminal 11 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF/Vehicle OFF.
    2. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K96 Mirror Control Module.
    • Go to next step: If less than 10 Ω 
  7. Ignition ON/Vehicle in Service Mode.
  8. Test for 4.8 - 5.2 V between the signal circuit terminal 5 and ground.
    • If less than 4.8 V 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K96 Mirror Control Module.
    • If greater than 5.2 V 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K96 Mirror Control Module.
    • Go to next step: If between 4.8 - 5.2 V 
  9. Test for 4.8 - 5.2 V between the signal circuit terminal 12 and ground.
    • If less than 4.8 V 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for infinite resistance between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K96 Mirror Control Module.
    • If greater than 5.2 V 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K96 Mirror Control Module.
    • Go to next step: If between 4.8 - 5.2 V 
  10. Test or replace the S52 Outside Rearview Mirror Switch.

Driver Outside Mirror Movement Malfunction

  1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the A9A Outside Rearview Mirror-Driver. Ignition ON/Vehicle in Service Mode.
  2. Connect a test lamp between the control circuit terminal 11 and control circuit terminal 16.
  3. Verify the test lamp turns ON when commanding the Up and Down states with a scan tool.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for infinite resistance between each control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: 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, replace the K96 Mirror Control Module.
    • If the test lamp is always ON 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the harness connector at the K96 Mirror Control Module, 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, replace the K96 Mirror Control Module
    • Go to next step: If the test lamp turns ON during each of the commands 
  4. Connect a test lamp between the control circuit terminal 14 and control circuit terminal 16.
  5. Verify the test lamp turns ON when commanding the Left and Right states with a scan tool.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for infinite resistance between each control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: 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, replace the K96 Mirror Control Module.
    • If the test lamp is always ON 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the harness connector at the K96 Mirror Control Module, 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, replace the K96 Mirror Control Module
    • Go to next step: If the test lamp turns ON during each of the commands 
  6. Test or replace the M77D Outside Rearview Mirror Motor-Driver.

Driver Mirror Position Sensor Circuit Test

  1. Ignition OFF/Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the A9A Outside Rearview Mirror-Driver. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the low reference circuit terminal 3 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K96 Mirror Control Module.
    • Go to next step: If less than 10 Ω 
  3. Ignition ON/Vehicle in Service Mode.
  4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 21 and ground.
    • If less than 4.8 V 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for infinite resistance between the 5 V reference circuit terminal 21 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the 5 V reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K96 Mirror Control Module.
    • If greater than 5.2 V 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module, ignition ON.
    2. Test for less than 1 V between the 5 V reference circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K96 Mirror Control Module.
    • Go to next step: If between 4.8 - 5.2 V 
  5. Verify the scan tool Driver Mirror Vertical Position parameter is less than 4.6 V.
    • If 4.6 V or greater 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal 13 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K96 Mirror Control Module.
    • Go to next step: If less than 4.6 V 
  6. Install a 3 A fused jumper wire between the signal circuit terminal 18 and the 5 V reference circuit terminal 21.
  7. Verify the scan tool Driver Mirror Vertical Position or the parameter is greater than 0.6 V.
    • If 0.6 V or less 
    1. Ignition OFF/Vehicle OFF, remove the jumper wire, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for infinite resistance between the signal circuit terminal 13 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K96 Mirror Control Module.
    • Go to next step: If greater than 0.6 V 
  8. Verify the scan tool Driver Mirror Horizontal Position parameter is less than 4.6 V.
    • If 4.6 V or greater 
    1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the K96 Mirror Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal 4 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K96 Mirror Control Module.
    • Go to next step: If less than 4.6 V 
  9. Install a 3 A fused jumper wire between the signal circuit terminal 9 and the 5 V reference circuit terminal 21.
  10. Verify the scan tool Driver Mirror Horizontal Position or the parameter is greater than 0.6 V.
    • If 0.6 V or less 
    1. Ignition OFF/Vehicle OFF, remove the jumper wire, disconnect the harness connector at the K96 Mirror Control Module.
    2. Test for infinite resistance between the signal circuit terminal 4 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K96 Mirror Control Module.
    • Go to next step: If greater than 0.6 V 
  11. Test or replace the M77D Outside Rearview Mirror Motor-Driver.

Passenger Outside Mirror Movement Malfunction

  1. Ignition OFF/Vehicle OFF, disconnect the harness connector at the A9B Outside Rearview Mirror-Passenger. Ignition ON/Vehicle in Service Mode
  2. Connect a test lamp between the control circuit terminal 11 and control circuit terminal 16.
  3. Verify the test lamp turns ON when commanding the Up and Down states with a scan tool.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the X2 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.
      • Go to next step: 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, replace the S79P Window Switch-Passenger.
    • If the test lamp is always ON 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the X2 harness connector at the S79P Window Switch-Passenger, 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, replace the S79P Window Switch-Passenger
    • Go to next step: If the test lamp turns ON during each of the commands 
  4. Connect a test lamp between the control circuit terminal 14 and control circuit terminal 16.
  5. Verify the test lamp turns ON when commanding the Left and Right states with a scan tool.
    • If the test lamp remains OFF during either of the commands 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the X2 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.
      • Go to next step: 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, replace the S79P Window Switch-Passenger.
    • If the test lamp is always ON 
    1. Ignition OFF/Vehicle OFF, remove the test lamp, disconnect the X2 harness connector at the S79P Window Switch-Passenger, 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, replace the S79P Window Switch-Passenger
    • Go to next step: If the test lamp turns ON during each of the commands 
  6. Test or replace the M77P Outside Rearview Mirror Motor-Passenger.

Passenger Mirror Position Sensor Circuit Test

  1. Ignition OFF/Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the A9B Outside Rearview Mirror-Passenger. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the low reference circuit terminal 3 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF/Vehicle OFF, disconnect the X2 harness connector at the S79P Window Switch-Passenger.
    2. Test for less than 2 Ω in the low reference 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.
    • Go to next step: If less than 10 Ω 
  3. Ignition ON/Vehicle in Service Mode.
  4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 21 and ground.
    • If less than 4.8 V 
    1. Ignition OFF/Vehicle OFF, disconnect the X2 harness connector at the S79P Window Switch-Passenger.
    2. Test for infinite resistance between the 5 V reference circuit terminal 4 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the 5 V reference 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 greater than 5.2 V 
    1. Ignition OFF/Vehicle OFF, disconnect the X2 harness connector at the S79P Window Switch-Passenger, ignition ON.
    2. Test for less than 1 V between the 5 V reference circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the S79P Window Switch-Passenger.
    • Go to next step: If between 4.8 - 5.2 V 
  5. Verify the scan tool Passenger Mirror Vertical Position parameter is less than 4.6 V.
    • If 4.6 V or greater 
    1. Ignition OFF/Vehicle OFF, disconnect the X2 harness connector at the S79P Window Switch-Passenger, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal 5 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the S79P Window Switch-Passenger.
    • Go to next step: If less than 4.6 V 
  6. Install a 3 A fused jumper wire between the signal circuit terminal 18 and the 5 V reference circuit terminal 21.
  7. Verify the scan tool Passenger Mirror Vertical Position or the parameter is greater than 0.6 V.
    • If 0.6 V or less 
    1. Ignition OFF/Vehicle OFF, remove the jumper wire, disconnect the X2 harness connector at the S79P Window Switch-Passenger.
    2. Test for infinite resistance between the signal circuit terminal 5 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the signal 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.
    • Go to next step: If greater than 0.6 V 
  8. Verify the scan tool Passenger Mirror Horizontal Position parameter is less than 4.6 V.
    • If 4.6 V or greater 
    1. Ignition OFF/Vehicle OFF, disconnect the X2 harness connector at the S79P Window Switch-Passenger, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal 11 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the S79P Window Switch-Passenger.
    • Go to next step: If less than 4.6 V 
  9. Install a 3 A fused jumper wire between the signal circuit terminal 9 and the 5 V reference circuit terminal 21.
  10. Verify the scan tool Passenger Mirror Horizontal Position or the parameter is greater than 0.6 V.
    • If 0.6 V or less 
    1. Ignition OFF/Vehicle OFF, remove the jumper wire, disconnect the X2 harness connector at the S79P Window Switch-Passenger.
    2. Test for infinite resistance between the signal circuit terminal 11 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the signal 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.
    • Go to next step: If greater than 0.6 V 
  11. Test or replace the M77P Outside Rearview Mirror Motor-Passenger.
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