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Circuit/System Testing

Only one camera image distorted

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the appropriate camera. 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 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, replace the K157 Video Processing Control Module.
    • 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 6 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 4
    • 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 4
    • 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:
    • B174G Frontview Camera - Grille video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 1 X1
    • B174G Frontview Camera - Grille video signal (+) circuit terminal 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 11 X1
    • 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 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 14 X1
    • B225L Sideview Camera - Left video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 5 X1
    • B225L Sideview Camera - Left video signal (+) circuit terminal 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 15 X1
    • B225R Sideview Camera - Right video signal (+) circuit terminal 1 and the K157 Video Processing Control Module video signal (+) circuit terminal 8 X1
    • B225R Sideview Camera - Right video signal (+) circuit terminal 4 and the K157 Video Processing Control Module video signal (+) circuit terminal 18 X1
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • Go to next step: If less than 2 Ω 
  10. Engine running, transmission in R.
  11. Verify a clear surround vision image is displayed on the P17 Info Display Module.
    • If a clear surround vision image is not displayed 
    1. Replace the appropriate camera.
    2. Engine running, transmission in R.
    3. Verify a clear surround vision image is displayed on the P17 Info Display Module.
      • If a clear surround vision image is not displayed, replace the K157 Video Processing Control Module.
      • If a clear surround vision image is displayed, all OK.
    • Go to next step: If a clear surround vision image is displayed 
  12. All OK.

All camera images distorted with IO3

  1. Attempt to communicate with the K157 Video Processing Control Module using the scan tool.
    • Go to next step: If K157 Video Processing Control Module does communicate with the scan tool 
  2. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K157 Video Processing Control Module. It may take up to 2 min for all vehicle systems to power down.
  3. Test for less than 1 V between the signal circuit terminals listed below and ground:
    • Camera signal (+) circuit terminal 6 X2
    • Camera signal (-) circuit terminal 12 X2
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • Go to next step: If less than 1 V 
  4. Test for infinite resistance between the signal circuit terminals listed below and ground:
    • Camera signal (+) circuit terminal 6 X2
    • Camera signal (-) circuit terminal 12 X2
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  5. Test for less than 2 Ω between the camera signal (+) circuit terminal 6 X2 and the A11 Radio video signal (+) circuit terminal 5 X1.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • Go to next step: If less than 2 Ω 
  6. Test for less than 2 Ω between the camera signal (-) circuit terminal 12 X2 and the A11 Radio video signal (-) circuit terminal 4 X1.
    • If 2 Ω or greater 

      Test the signal circuit for an open/high resistance.

    • Go to next step: If less than 2 Ω 
  7. Replace the K157 Video Processing Control Module.
  8. Engine running, transmission in R.
  9. Verify a clear surround vision image is displayed on the P17 Info Display Module.
    • If a clear rear vision image is not displayed 

      Replace the A11 Radio.

    • Go to next step: If a clear rear vision image is displayed 
  10. All OK.

All camera images distorted with IO5 or IO6

  1. Attempt to communicate with the K157 Video Processing Control Module using the scan tool.
    • Go to next step: If K157 Video Processing Control Module does communicate with the scan tool 
  2. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K157 Video Processing Control Module. It may take up to 2 min for all vehicle systems to power down.
  3. Test for less than 1 V between the signal circuit terminals listed below and ground:
    • Camera signal (+) circuit terminal 6 X2
    • Camera signal (-) circuit terminal 12 X2
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • Go to next step: If less than 1 V 
  4. Ignition OFF, disconnect the K74 Human Machine Interface Control Module X2 harness connector.
  5. Test for infinite resistance between the signal circuit terminals at the K157 Video Processing Control Module harness connector listed below and ground:
    • Camera signal (+) circuit terminal 6 X2
    • Camera signal (-) circuit terminal 12 X2
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • Go to next step: If infinite resistance 
  6. Test for less than 2 Ω between the camera signal (+) circuit terminal 6 X2 and the K74 Human Machine Interface Control Module video signal (+) circuit terminal 5 X2.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • Go to next step: If less than 2 Ω 
  7. Test for less than 2 Ω between the camera signal (-) circuit terminal 12 X2 and the K74 Human Machine Interface Control Module video signal (-) circuit terminal 6 X2.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • Go to next step: If less than 2 Ω 
  8. Replace the K157 Video Processing Control Module.
  9. Engine running, transmission in R.
  10. Verify a clear surround vision image is displayed on the P17 Info Display Module.
    • If a clear rear vision image is not displayed 

      Replace the K74 Human Machine Interface Control Module.

    • Go to next step: If a clear rear vision image is displayed 
  11. All OK.
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