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Home >> Buick >> 2017 >> Envision Essence, FWD >> Repair and Diagnosis >> Accessories & Equipment >> Collision/Avoidance >> Object Detection System And Pedestrian Protection System >> Diagnostic Information and Procedures >> Side Blind Zone Alert System Malfunction >> Circuit/System Testing
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Circuit/System Testing

Left Side Object Sensor Malfunction

  1. Ignition OFF and all vehicle systems OFF. Disconnect the harness connector at the B218L Side Object Sensor Module - Left. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between ground circuit terminal 8 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 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 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 B218L Side Object Sensor Module - Left.
    • If the test lamp illuminates 
  4. Ignition OFF and all vehicle systems OFF. Disconnect the It may take up to 2 minutes for all vehicle systems to power down.
  5. Test for less than 2 Ω between the serial data circuit terminal 2 and the DLC terminal 1.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 2 Ω 
  6. Replace B218L Side Object Sensor Module - Left.

Right Side Object Sensor Malfunction

  1. Ignition OFF and all vehicle systems OFF. Disconnect the harness connector at the B218R Side Object Sensor Module - Right. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the following ground circuit terminals and ground.
    • Terminal 3
    • Terminal 8
    • 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 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 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 B218R Side Object Sensor Module - Right.
    • If the test lamp illuminates 
  4. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.
  5. Test for less than 2 Ω between the serial data circuit terminal 7 and the DLC terminal 1.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 2 Ω 
  6. Replace B218R Side Object Sensor Module - Right.

Side Object Indicator Malfunction

  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector for the appropriate A9 Outside Rearview Mirror. It may take up to 2 min for all vehicle systems to power down.
    • X510 - Driver Door Harness to Outside Rearview Mirror
    • X610 - Passenger Door Harness to Outside Rearview Mirror
  2. Test for less than 10 Ω between the ground circuit terminal 12 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, connect a test lamp between the control circuit terminal 11 and the ground circuit terminal 12.
  4. Verify the test lamp turns ON and OFF when commanding the appropriate Object Detection Alert Indicators ON and OFF with a scan tool.
    • If the test lamp is always OFF 
    1. Ignition OFF, disconnect the harness connector at the appropriate B218 Side Object Sensor Module.
    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
    3. 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 B218 Side Object Sensor Module.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the harness connector at the B218 Side Object Sensor Module, 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, replace the B218 Side Object Sensor Module.
    • If the test lamp turns ON and OFF 
  5. Test or replace the A9 Outside Rearview Mirror Glass.
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