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Home >> Cadillac >> 2015 >> XTS Base >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Collision/Avoidance >> Object Detection System And Pedestrian Protection System >> Diagnostic Information and Procedures >> Forward Collision Alert System Malfunction >> Circuit/System Testing
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Circuit/System Testing

NOTE:

Perform the Circuit/System Verification before proceeding with Circuit/System Testing.

Frontview Camera Module Malfunction without Active Safety System, UGN

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K109 Frontview Camera Module. 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 1 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. Verify a test lamp illuminates between the B+ circuit terminal 3 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 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.
    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 K109 Frontview Camera Module.
    • If the test lamp illuminates 
  4. Replace the K109 Frontview Camera Module.

Frontview Camera Module Malfunction with Active Safety System, UGN

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K109 Frontview Camera Module. 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, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Verify a test lamp illuminates between the B+ circuit terminal 2 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 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.
    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 K109 Frontview Camera Module.
    • If the test lamp illuminates 
  4. Replace the K109 Frontview Camera Module.

Forward Collision Alert Indicator Malfunction

  1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at the P43 Collision Alert Indicators. 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.
    • If less than 10 Ω 
  3. Ignition ON.
  4. Verify a test lamp illuminates between the ignition circuit terminal 1 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, 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 P43 Collision Alert Indicators.
    • If the test lamp illuminates 
  5. Connect a test lamp between the control circuit terminal 2 and the ignition circuit terminal 1.
  6. Verify the test lamp turns ON and OFF when commanding the Instrument Cluster All Indicators On and Off with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the harness connector at the P16 Instrument Cluster, ignition ON.
    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. Ignition OFF.
    4. 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 P16 Instrument Cluster.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the harness connector at the P16 Instrument Cluster.
    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, replace the P16 Instrument Cluster.
    • If the test lamp turns ON and OFF 
  7. Test or replace the P43 Collision Alert Indicators.

Forward Collision Alert Switch Malfunction

  1. Ignition OFF, disconnect the X3 harness connector at the K9 Body Control Module, ignition ON.
  2. Test for less than 1 V between the signal circuit terminals listed below and ground:
    • Terminal 4
    • Terminal 16
    • If 1 V or greater 

      Repair the short to voltage on the signal circuit.

    • If less than 1 V 
  3. Ignition OFF.
  4. Test for infinite resistance between the signal circuit terminals listed below and ground:
    • Terminal 4
    • Terminal 16
    • If less than infinite resistance 

      Repair the short to ground on the signal circuit.

    • If infinite resistance 
  5. Test for 7.0k - 10.5k Ω between signal circuit terminals 4 and signal circuit terminal 16.
    • If greater than 10.5k Ω 
    1. Disconnect the harness connector at the S70L Steering Wheel Controls Switch - Left.
    2. Test for less than 5 Ω between the circuit terminals listed below:
      • S70L Steering Wheel Controls Switch - Left terminal 8 and K9 Body Control Module terminal 4.
      • S70L Steering Wheel Controls Switch - Left terminal 9 and K9 Body Control Module terminal 16.
      • If greater than 5 Ω, repair the open/high resistance in the circuit.
      • If less than 5 Ω, test or replace the S70L Steering Wheel Controls Switch - Left.
    • If less than 7.0k Ω 
    1. Disconnect the harness connector at the S70L Steering Wheel Controls Switch - Left.
    2. Verify infinite resistance between signal circuit terminals 4 and signal circuit terminal 16
      • If less than infinite resistance, repair short in circuit.
      • If infinite resistance, test or replace the S70L Steering Wheel Controls Switch - Left.
    • If between 7.0k - 10.5k Ω 
  6. Test for 2.1k - 3.2k Ω between signal circuit terminals 4 and signal circuit terminal 16 while pressing forward collision alert switch.
    • If not between 2.1k - 3.2k Ω 

      Test or replace the S70L Steering Wheel Controls Switch - Left.

    • If between 2.1k - 3.2k Ω 
  7. Replace the K9 Body Control Module.
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