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Home >> Cadillac >> 2017 >> XT5 Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Wiper/Washer Systems >> Wiper System And Washer System >> Diagnostic Information and Procedures >> Windshield Wiper System Malfunction >> Circuit/System Testing
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Circuit/System Testing

Windshield Wiper Switch Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S82 Windshield Wiper/Washer Switch. It may take up to 11 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the low reference circuit terminal 1 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the K9 Body 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 K9 Body Control Module.
    • If less than 10 Ω 
  3. Ignition ON.
  4. Verify the scan tool Windshield Wiper High Speed Switch parameter is Inactive.
    • If not Inactive 
    1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the signal circuit terminal 2 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K9 Body Control Module.
    • If Inactive 
  5. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the low reference circuit terminal 1.
  6. Verify the scan tool Windshield Wiper High Speed Switch parameter is Active.
    • If not Active 
    1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K9 Body 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
    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 K9 Body Control Module.
    • If Active 
  7. Test for greater than 8 V between the signal circuit terminal 3 and ground.
    • If less than 8 V 
    1. Ignition OFF, disconnect the harness connector at the K9 Body 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.
      • 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 K9 Body Control Module.
    • If 8 V or greater 
  8. Ignition OFF, disconnect the X3 harness connector at the K9 Body Control Module, ignition ON.
  9. Test for less than 1 V between the S82 Windshield Wiper/Washer Switch signal circuit terminal 3 and ground.
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • If less than 1 V 
  10. Test or replace the S82 Windshield Wiper/Washer Switch.

Windshield Wiper Motor Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the X2 harness connector at the X50A Fuse Block - Underhood. It may take up to 10 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 38 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. Connect the X2 harness connector at the X50A Fuse Block - Underhood, disconnect the harness connector at the M75 Windshield Wiper Motor.
  4. Test for less than 10 Ω between the ground circuit terminal 5 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 
  5. Ignition ON.
  6. Verify the scan tool Windshield Wiper Park Switch parameter is Inactive.
    • If not Inactive 
    1. Ignition OFF, disconnect the X4 harness connector at the K9 Body Control Module.
    2. Test for infinite resistance between the M75 Windshield Wiper Motor park switch signal circuit terminal 3 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K9 Body Control Module.
    • If Inactive 
  7. Install a 3 A fused jumper wire between the signal circuit terminal 3 and ground circuit terminal 5.
  8. Verify the scan tool Windshield Wiper Park Switch parameter is Active.
    • If not Active 
    1. Ignition OFF, remove the jumper wire, disconnect the X4 harness connector at the K9 Body 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
    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 K9 Body Control Module.
    • If Active 
  9. Connect a test lamp between the following control circuits and ground, ignition ON.
    • Windshield Wiper Motor Low Speed Control Circuit Terminal 1
    • Windshield Wiper Motor High Speed Control Circuit Terminal 4
  10. Verify the test lamp does NOT turn ON and OFF when commanding the Windshield Wiper Relay High and Low with a scan tool.
    • If the test lamp turns ON and OFF for both terminals 

      Test or replace the M75 Windshield Wiper Motor.

    • If the test lamp does not turn ON and OFF for one or both terminals 
  11. Ignition OFF, connect the harness connector at the M75 Windshield Wiper Motor. Disconnect the X2 harness connector at the X50A Fuse Block - Underhood.
  12. Connect a 20 A fused jumper wire between the control circuit terminals listed below, one at a time, and B+.
    • Terminal 20
    • Terminal 19
  13. Verify the M75 Windshield Wiper Motor activates.
    • If the M75 Windshield Wiper Motor does not activate 
    1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the M75 Windshield Wiper Motor.
    2. Test for infinite resistance between the 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 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 M75 Windshield Wiper Motor.
    • If the M75 Windshield Wiper Motor activates 
  14. Ignition OFF, connect the X2 harness connector at the X50A Fuse Block - Underhood. Disconnect the X4 harness connector at the K9 Body Control Module, ignition ON.
  15. Verify the M75 Windshield Wiper Motor low speed is not activated.
    • If the M75 Windshield Wiper Motor low speed is activated 
    1. Ignition OFF, disconnect the X2 harness connector at the X50A Fuse Block - Underhood, ignition ON.
    2. Test for less than 1 V between the control circuit terminal 16 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, test or replace the replace the X50A Fuse Block - Underhood.
    • If the M75 Windshield Wiper Motor low speed is not activated 
  16. Ignition OFF, disconnect the X2 harness connector at the K9 Body Control Module, ignition ON.
  17. Verify the M75 Windshield Wiper Motor High Speed is not activated.
    • If the M75 Windshield Wiper Motor high speed is activated 
    1. Ignition OFF, disconnect the X2 harness connector at the X50A Fuse Block - Underhood, ignition ON.
    2. Test for infinite resistance between the control circuit terminal 14 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the X50A Fuse Block - Underhood.
    • If the M75 Windshield Wiper Motor high speed is not activated 
  18. Connect a 10 A fused jumper wire between the control circuit terminal 16 X4 and B+.
  19. Verify the M75 Windshield Wiper Motor activates.
    • If the M75 Windshield Wiper Motor does not activate 
    1. Ignition OFF, remove the jumper wire, disconnect the X2 harness connector at the X50A Fuse Block - Underhood.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If less than infinite resistance
    3. 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, test or replace the X50A Fuse Block - Underhood.
    • If the M75 Windshield Wiper Motor activates 
  20. Connect a 10 A fused jumper wire between the control circuit terminal 24 X5 and ground.
  21. Verify the M75 Windshield Wiper Motor activates.
    • If the M75 Windshield Wiper Motor does not activate 
    1. Ignition OFF, remove the jumper wire, disconnect the X2 harness connector at the X50A Fuse Block - Underhood.
    2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    3. 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, test or replace the X50A Fuse Block - Underhood.
    • If the M75 Windshield Wiper Motor activates 
  22. Replace the K9 Body Control Module.
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