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Home >> GMC >> 2019 >> Terrain SL >> Repair and Diagnosis >> External Pages >> Different car >> Section 82 (Image Display Camera System) >> Diagnostic Information And Procedures >> Rear Vision Camera System Malfunction (IO5/IO6 With MAH/MBC) >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page is about a different car, the 2018 GMC Terrain and 2018 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.

Circuit/System Testing- A: Info Display does not Display Radio Information

  1. Ignition OFF, disconnect the K74 Human Machine Interface Control Module X5 and the K188 Human Machine Interface Control Module Bypass Module harness connector X2.
  2. Connect the EL-50334-2 to the K74 Human Machine Interface Control Module connector X5 and EL-50334-14 to the K188 Human Machine Interface Control Module Bypass Module connector X2. Connect EL-50334-2 and EL-50334-14 together.
  3. Ignition ON/Vehicle in Service Mode, infotainment system ON.
  4. Verify the P17 Info Display Module displays and image.
    • If the P17 Info Display Module does not display an image. 

      Replace the K74 Human Machine Interface Control Module.

    • Go to next step: If the P17 Info Display Module displays an image. 
  5. Replace the USB harness between the K74 Human Machine Interface Control Module to the K188 Human Machine Interface Control Module Bypass Module.

Circuit/System Testing - B: Info Display Module does not Display Anything

  1. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down. Disconnect K188 Human Machine Interface Control Module Bypass Module harness connector X1.
  2. Test for less than 10 Ω between the K188 Human Machine Interface Control Module Bypass Module ground circuit terminal 5 X1 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.

    • Go to next step: If less than 10 Ω 
  3. Verify a test lamp illuminates between the B+ circuit terminal 1 X1 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 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 OK and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition 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.
      • If infinite resistance, replace the K188 Human Machine Interface Control Module Bypass Module.
    • Go to next step: If the test lamp illuminates 
  4. Ignition ON.
  5. Verify a test lamp illuminates between the ignition circuit terminal 2 X1 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 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. Refer to Power Mode Mismatch .
    • 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, replace the K188 Human Machine Interface Control Module Bypass Module.
    • Go to next step: If the test lamp illuminates 
  6. Engine running, parking brake applied, transmission in REVERSE.
  7. Verify a test lamp illuminates between the control circuit terminal 9 X1 and ground.
    • If the test lamp does not illuminate 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the control circuit end to end.
    • Go to next step: If the test lamp illuminates 
  8. Reconnect the K188 Human Machine Interface Control Module Bypass Module.
  9. Ignition OFF, disconnect the P17 Info Display Module connector X3 and the K188 Human Machine Interface Control Module Bypass Module connector X3.
  10. Ignition OFF, connect the EL-50334-14 to the P17 Info Display Module X3 and EL-50334-2 to the K188 Human Machine Interface Control Module Bypass Module connector X3. Connect EL-50334-2 and EL-50334-14 together.
  11. Engine running, parking brake applied, transmission in REVERSE.
  12. Verify the rear view image displays properly.
    • If the image displays properly 

      Replace the USB harness between the P17 Info Display Module connector X3 and the K188 Human Machine Interface Control Module Bypass Module connector X3.

    • Go to next step: If the image does not display properly 
  13. Ignition OFF, disconnect the K74 Human Machine Interface Control Module X5.
  14. Connect the EL-50334-2 to the K74 Human Machine Interface Control Module connector X5 and connect the EL-50334-14 to the P17 Info Display Module X3. Connect EL-50334-2 and EL-50334-14 together.
  15. Engine running, parking brake applied, transmission in REVERSE.
  16. Verify the rear view image displays properly.
    • If rear view image displays properly 

      Replace the K188 Human Machine Interface Control Module Bypass Module.

    • Go to next step: If the rear view image does not display properly 
  17. Replace the P17 Info Display Module.
  18. Engine running, parking brake applied, transmission in REVERSE.
  19. Verify the rear view image displays properly.
    • If rear view image is not displayed 

      Replace the B87 Rearview Camera.

    • Go to next step: If rear view image is displayed 
  20. All OK.

Circuit/System Testing - C: No Rear View Camera Image

  1. Ignition OFF and all vehicle systems OFF, disconnect the B87 Rearview Camera harness connector It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 4 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.

    • Go to next step: If less than 10 Ω 
  3. Ignition ON.
  4. Verify a test lamp illuminates between the ignition circuit terminal 5 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 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. Refer to Power Mode Mismatch .
    • 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, replace the B87 Rearview Camera.
    • Go to next step: If the test lamp illuminates 
  5. Ignition OFF, disconnect the X1 harness connector at the K188 Human Machine Interface Control Module Bypass Module, ignition ON.
  6. Test for less than 1 V between the signal circuit terminals listed below and ground:
    • K188 Human Machine Interface Control Module Bypass Module signal (+) circuit terminal 6 X1
    • K188 Human Machine Interface Control Module Bypass Module signal (-) circuit terminal 18 X1
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • Go to next step: If less than 1 V 
  7. Ignition OFF.
  8. Test for infinite resistance between the signal circuit terminals listed below and ground:
    • K188 Human Machine Interface Control Module Bypass Module signal (+) circuit terminal 6 X1
    • K188 Human Machine Interface Control Module Bypass Module signal (-) circuit terminal 18 X1
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  9. Test for less than 2 Ω between the K188 Human Machine Interface Control Module Bypass Module signal (+) circuit terminal 6 X1 and the other end of the circuit.
    • If 2 Ω or greater 

      Repair the open/high resistance on the circuit.

    • Go to next step: If less than 2 Ω 
  10. Test for less than 2 Ω between the K188 Human Machine Interface Control Module Bypass Module signal (-) circuit terminal 18 X1 and the other end of the circuit.
    • If 2 Ω or greater 

      Repair the open/high resistance on the circuit.

    • Go to next step: If less than 2 Ω 
  11. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.
  12. Test for less than 10 Ω between the K188 Human Machine Interface Control Module Bypass Module ground circuit terminal 5 X1 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.

    • Go to next step: If less than 10 Ω 
  13. Verify a test lamp illuminates between the B+ circuit terminal 1 X1 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 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 OK and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Ignition 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.
      • If infinite resistance, replace the K188 Human Machine Interface Control Module Bypass Module.
    • Go to next step: If the test lamp illuminates 
  14. Ignition ON.
  15. Verify a test lamp illuminates between the ignition circuit terminal 2 X1 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 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. Refer to Power Mode Mismatch .
    • 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, replace the K188 Human Machine Interface Control Module Bypass Module.
    • Go to next step: If the test lamp illuminates 
  16. Engine running, parking brake applied, transmission in REVERSE.
  17. Verify a test lamp illuminates between the control circuit terminal 9 X1 and ground.
    • If the test lamp does not illuminate 
    1. Ignition OFF.
    2. Test for less than 2 Ω in the control circuit end to end.
    • Go to next step: If the test lamp illuminates 
  18. Reconnect the K188 Human Machine Interface Control Module Bypass Module.
  19. Ignition OFF, disconnect the P17 Info Display Module connector X3 and the K188 Human Machine Interface Control Module Bypass Module connector X3.
  20. Ignition OFF, connect the EL-50334-2 to the P17 Info Display Module connector X3 and EL-50334-14 to the K188 Human Machine Interface Control Module Bypass Module connector X3. Connect EL-50334-2 and EL-50334-14 together.
  21. Engine running, parking brake applied, transmission in REVERSE.
  22. Verify the rear view image displays properly.
    • If the image displays properly 

      Replace the USB harness between the P17 Info Display Module connector X3 and the K188 Human Machine Interface Control Module Bypass Module connector X3.

    • Go to next step: If the image does not display properly 
  23. Ignition OFF, disconnect the K74 Human Machine Interface Control Module X5.
  24. Connect the EL-50334-14 to the K74 Human Machine Interface Control Module connector X5 and connect the EL-50334-2 to the P17 Info Display Module connector X3. Connect EL-50334-2 and EL-50334-14 together.
  25. Engine running, parking brake applied, transmission in REVERSE.
  26. Verify the rear view image displays properly.
    • If rear view image displays properly 

      Replace the K188 Human Machine Interface Control Module Bypass Module.

    • Go to next step: If the rear view image does not display properly 
  27. Replace the P17 Info Display Module.
  28. Engine running, parking brake applied, transmission in REVERSE.
  29. Verify the rear view image displays properly.
    • If rear view image is not displayed 

      Replace the B87 Rearview Camera.

    • Go to next step: If rear view image is displayed 
  30. All OK.

Circuit/System Testing - D: No Enhanced Rear View Camera Image

  1. Ignition OFF, disconnect the K74 Human Machine Interface Control Module X1 harness connector. Ignition ON.
  2. Verify a test lamp illuminates between serial data communication enable circuit terminal 5 and ground.
    • If the test lamp does not illuminate 
    1. Ignition/Vehicle OFF.
    2. Test for infinite resistance between the serial data communication enable 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 serial data communication enable circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the control module that controls the serial data communication enable circuit.
    • Go to next step: If the test lamp illuminates 
  3. Ignition OFF, Connect the K74 Human Machine Interface Control Module X1 harness connector.
  4. Disconnect the K74 Human Machine Interface Control Module X2 harness connector and K188 Human Machine Interface Control Module Bypass Module X1 harness connector. Ignition ON.
  5. Test for less than 1 V between the signal circuit terminals listed below and ground:
    • K188 Human Machine Interface Control Module Bypass Module signal (+) circuit terminal 8 X1
    • K188 Human Machine Interface Control Module Bypass Module signal (-) circuit terminal 20 X1
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • Go to next step: If less than 1 V 
  6. Ignition OFF.
  7. Test for infinite resistance between the signal circuit terminals listed below and ground:
    • K188 Human Machine Interface Control Module Bypass Module signal (+) circuit terminal 8 X1
    • K188 Human Machine Interface Control Module Bypass Module signal (-) circuit terminal 20 X1
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  8. Test for less than 2 Ω between the K188 Human Machine Interface Control Module Bypass Module signal (+) circuit terminal 8 X1 and the K74 Human Machine Interface Control Module signal (+) circuit terminal 5 X2.
    • If 2 Ω or greater 

      Repair the open/high resistance on the circuit.

    • Go to next step: If less than 2 Ω 
  9. Test for less than 2 Ω between the K188 Human Machine Interface Control Module Bypass Module signal (-) circuit terminal 20 X1 and the K74 Human Machine Interface Control Module signal (+) circuit terminal 6 X2.
    • If 2 Ω or greater 

      Repair the open/high resistance on the circuit.

    • Go to next step: If less than 2 Ω 
  10. Ignition ON.
    11. NOTE:

    For accurate voltage reading, disconnect the battery charger prior to performing the following test step.

  11. Test for 2 - 12 V between the K188 Human Machine Interface Control Module Bypass Module LIN serial data circuit terminal 3 X1 and ground.
    • If less than 2 V 
    1. Ignition OFF.
    2. Test for infinite resistance between the serial data 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 serial data circuit end to each end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω
    4. Replace P17 Info Display Module.
    5. Reconnect the K74 Human Machine Interface Control Module, ignition ON.
    6. Test for 2 - 12 V between the LIN serial data circuit terminal and ground.
      • If less than 2 V, replace the K74 Human Machine Interface Control Module.
      • If greater than 2 V, replace the K188 Human Machine Interface Control Module Bypass Module.
    • If greater than 12 V 
    1. Ignition OFF, disconnect the X1 harness connector at the P17 Info Display Module.
    2. Ignition ON.
    3. Test for less than 1 V between the serial data circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V
    4. Replace P17 Info Display Module.
    5. Ignition OFF, reconnect the K74 Human Machine Interface Control Module, ignition ON.
    6. Test for 2 - 12 V between the LIN serial data circuit terminal and ground.
      • If greater than 12 V, replace the K74 Human Machine Interface Control Module.
      • If less than 12 V, replace the K188 Human Machine Interface Control Module Bypass Module.
    • Go to next step: If between 2 - 12 V 
  12. Re-connect the K74 Human Machine Interface Control Module and the K188 Human Machine Interface Control Module Bypass Module harness connectors.
  13. Ignition OFF, disconnect the K74 Human Machine Interface Control Module X5 and the K188 Human Machine Interface Control Module Bypass Module harness connector X2.
  14. Connect the EL-50334-2 to the K74 Human Machine Interface Control Module connector X5 and EL-50334-14 to the K188 Human Machine Interface Control Module Bypass Module connector X2. Connect EL-50334-2 and EL-50334-14 together.
  15. Engine running, parking brake applied, transmission in REVERSE.
  16. Verify the enhanced rear view image displays properly.
    • If the enhanced image displays properly 

      Replace the USB harness between the K74 Human Machine Interface Control Module X5 and the K188 Human Machine Interface Control Module Bypass Module harness connector X2.

    • Go to next step: If the enhanced image does not display properly 
  17. Ignition OFF, remove the EL-50334-14 from the K188 Human Machine Interface Control Module Bypass Module harness connector X2 and EL-50334-2 from the K74 Human Machine Interface Control Module connector X5.
  18. Re-connect the K188 Human Machine Interface Control Module Bypass Module harness connector X2.
  19. Disconnect the P17 Info Display Module harness connector X3.
  20. Connect the EL-50334-2 to the K74 Human Machine Interface Control Module connector X5 and EL-50334-14 to the P17 Info Display Module X3. Connect EL-50334-2 and EL-50334-14 together.
  21. Engine running, parking brake applied, transmission in REVERSE.
  22. Verify the enhanced image displays properly.
    • If the enhanced image displays properly 

      Replace the K188 Human Machine Interface Control Module Bypass Module.

    • Go to next step: If the enhanced image does not display properly 
  23. Replace the K74 Human Machine Interface Control Module.
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