LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 2016 >> Trax LS, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Data Communication System >> Diagnostic Information and Procedures >> DTC U18A6: Lost Communication with Right Object Detection Control Module >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

NOTE:

Use the schematics and connector end views to identify the device's ground, B+, and serial data circuit terminals.

  1. Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. 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 each ground circuit terminal and ground.
    • If 10 Ω or greater 
    1. Ignition/Vehicle 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/Vehicle In Service Mode.
  4. If equipped, verify a test lamp illuminates between each B+ circuit terminal and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Ignition/Vehicle 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/Vehicle 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 
  5. If equipped, test for at least 6 V between the communication enable circuit terminal and ground.
    • If less than 6 V 
    1. Ignition/Vehicle OFF, disconnect the harness connectors at the B218L Side Object Sensor Module - Left.
    2. Test for infinite resistance between the communication enable circuit terminal 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 communication enable circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the B218L Side Object Sensor Module - Left.
    • If 6 V or greater 
  6. Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. 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.
  7. Test for less than 1 V between each serial data circuits and ground.
    • If 1 V or greater 

      Repair the short to voltage in the serial data circuit.

    • If less than 1 V 
  8. Test for infinite resistance between each serial data circuits and ground.
    • If less than infinite resistance 

      Repair the short to ground in the serial data circuit.

    • If infinite resistance 
  9. Test for infinite resistance between 2 serial data circuits.
    • If less than infinite resistance 

      Repair the short together between the serial data circuits.

    • If infinite resistance 
  10. Test for less than 2 Ω in each of the serial data circuits end to end between the B218L Side Object Sensor Module - Left and the B218R Side Object Sensor Module - Right.
    • If 2 Ω or greater 

      Repair the open/high resistance in the serial data circuit.

    • If less than 2 Ω 
  11. NOTE:

    Prior to replacing a module, visually inspect wiring connections to both Side Object Sensor Modules for contamination, deformation, terminal fretting corrosion, terminal tension, and chafing.

  12. Replace the B218R Side Object Sensor Module - Right.