SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET2018TAHOE FL, 4WD, GASREPAIR AND DIAGNOSISENGINE PERFORMANCETESTING & DIAGNOSISDATA COMMUNICATION SYSTEM - DIAGNOSTIC INFORMATION AND PROCEDURESDIAGNOSTIC INFORMATION AND PROCEDURESDTC U18A6: LOST COMMUNICATION WITH RIGHT OBJECT DETECTION CONTROL MODULE ON DEDICATED BUS 1CIRCUIT/SYSTEM TESTING
2018 Chevrolet Tahoe FL, 4WD, Gas

Circuit/System Testing

2018 Chevrolet Tahoe FL, 4WD, GasSECTION 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 10 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.
    • Go to next step: 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, remove the test lamp.
    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, remove the test lamp.
    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.
    • Go to next step: 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.
    • Go to next step: 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 10 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.

    • Go to next step: 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.

    • Go to next step: 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.

    • Go to next step: 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.

    • Go to next step: 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.

  11. Replace the B218R Side Object Sensor Module - Right.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.