LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2019 >> Envision Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 21 (Image Display Camera System) >> Diagnostic Information and Procedures >> Rear Vision Camera System Malfunction (with UVH) >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2018 Buick Envision. 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 K48 Infotainment Faceplate Control Module displays and image.
    • If the K48 Infotainment Faceplate Control Module does not display an image. 

      Replace the K74 Human Machine Interface Control Module.

    • Go to next step: If the K48 Infotainment Faceplate Control 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.
  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.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is good and there is voltage at the fuse. Refer to Backup Lamps Malfunction .
    • 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 K48 Infotainment Faceplate Control Module connector X2 and the K188 Human Machine Interface Control Module Bypass Module connector X3.
  10. Ignition OFF, connect the EL-50334-15 orange end to the K48 Infotainment Faceplate Control Module connector X2 and EL-50334-15 B1 end (short end) to the K188 Human Machine Interface Control Module Bypass Module connector X3.
  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 K48 Infotainment Faceplate Control Module connector X2 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-50334-15 B1 end (short end) to the K74 Human Machine Interface Control Module connector X5 and connect the EL-50334-15 orange end to the K48 Infotainment Faceplate Control Module connector X2.
  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 K48 Infotainment Faceplate Control 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. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 5 and ground.
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the harness connector at the K157 Video Processing Control Module.
    2. Test for infinite resistance between the 5 V reference 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 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 K157 Video Processing Control Module.
    • If greater than 5.2 V 
    1. Ignition OFF, disconnect the harness connector at the K157 Video Processing 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 K157 Video Processing Control Module.
    • Go to next step: If between 4.8 - 5.2 V 
  5. Ignition ON.
  6. Test for less than 10 V between the signal circuit terminals listed below and ground:
    • Vision Signal + signal circuit terminal 1
    • Vision Signal - signal circuit terminal 3
    • If 10 V or greater 
    1. Ignition OFF, disconnect the X1 harness connector at the K157 Video Processing 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 K157 Video Processing Control Module.
    • Go to next step: If less than 10 V 
  7. Ignition OFF.
  8. Test for infinite resistance between the signal circuit terminals listed below and ground:
    • Vision Signal + signal circuit terminal 1
    • Vision Signal - signal circuit terminal 3
    • If less than infinite resistance 
    1. Disconnect the X1 harness connector at the K157 Video Processing Control Module.
    2. Test for infinite between the signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K157 Video Processing Control Module.
    • Go to next step: If infinite resistance 
  9. Test for less than 2 Ω between the appropriate video signal circuit terminals listed below:
    • B87 Rearview Camera video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 4 X1
    • B87 Rearview Camera video signal (+) circuit terminal 3 and the K157 Video Processing Control Module video signal (+) circuit terminal 14 X1
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • Go to next step: If less than 2 Ω 
  10. Replace the B87 Rearview Camera.
  11. Engine running, parking brake applied, transmission in R.
  12. Verify a clear surround vision image is displayed on the K48 Infotainment Faceplate Control Module.
    • If a clear rear vision image is not displayed 

      Replace the K157 Video Processing Control Module.

    • Go to next step: If a clear rear vision image is displayed 
  13. 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.
      • Go to next step: 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.
      • Go to next step: 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.
      • Go to next step: If less than 2 Ω
    4. Replace K48 Infotainment Faceplate Control 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 K48 Infotainment Faceplate Control 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.
      • Go to next step: If less than 1 V
    4. Replace K48 Infotainment Faceplate Control 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 K48 Infotainment Faceplate Control Module harness connector X2.
  20. Connect the EL-50334-15 B1 end (short end) to the K74 Human Machine Interface Control Module connector X5 and EL-50334-15 orange end to the K48 Infotainment Faceplate Control Module X2.
  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.
scientia non olet · About LEMON Manuals