LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 2016 >> Envision >> Repair and Diagnosis >> External Pages >> Different car >> Section 199 (Object Detection System) >> Diagnostic Information and Procedures >> Side Object System Malfunction >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

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

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 7 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 8 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.
  5. Test for less than 2 Ω between the B218L Side Object Sensor Module - Left serial data circuit terminal 1 and the X84 Data Link Connector serial data circuit 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.

Side Object Indicator Malfunction

  1. Ignition OFF and all vehicle systems OFF, remove the appropriate outside rearview mirror glass. It may take up to 2 min for all vehicle systems to power down.
  2. Test for less than 10 Ω between the P34 Side Object Detection Indicator ground circuit terminal 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 P34 Side Object Detection Indicator control circuit terminal and ground.
  4. Verify the test lamp turns ON and OFF when commanding the 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 B218R Side Object Sensor Module - Right.
    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 B218R Side Object Sensor Module - Right.
    • If the test lamp is always ON 
    1. Ignition OFF, disconnect the harness connector at the B218R Side Object Sensor Module - Right, 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 B218R Side Object Sensor Module - Right.
    • If the test lamp turns ON and OFF 
  5. Test or replace the A9 Outside Rearview Mirror Glass.