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Home >> Cadillac >> 2017 >> ATS Base, 2D Coupe, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 264 (Object Detection System And Pedestrian Protection System - Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> Forward Collision Alert System Malfunction >> Circuit/System Testing
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Circuit/System Testing

WARNING: This page is about a different car, the 2016 Cadillac CT6. However, it is still accessible from the selected car via links, so may be relevant.

Frontview Camera Module Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B174W Frontview Camera - Windshield. 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 B174W Frontview Camera - Windshield.
    • If the test lamp illuminates 
  4. Replace the B174W Frontview Camera - Windshield.

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. Verify a test lamp illuminates between the control circuit terminal 2 and B+
    • If the test lamp does not illuminate 
    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 illuminates 
  6. Verify a test lamp illuminates between the control circuit terminal 3 and B+
    • If the test lamp does not illuminate 
    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 illuminates 
  7. Ignition OFF, connect the harness connector at the P43 Collision Alert Indicators, ignition ON.
  8. Verify the P43 Collision Alert Indicators are not illuminated.
    • If the P43 Collision Alert Indicators are illuminated 
    1. Ignition OFF, disconnect the harness connector at the P43 Collision Alert Indicators and the P16 Instrument Cluster.
    2. Test for infinite resistance between the P43 Collision Alert Indicators control circuit terminal 2 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 P43 Collision Alert Indicators are not illuminated 
  9. Test or replace the P43 Collision Alert Indicators.
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