2025 Chevrolet Trailblazer RS, 4WDFACTORY OEM SERVICE PROCEDURE

Circuit/System Testing

  1. Ignition/Vehicle & All vehicle systems - Off
  2. Disconnect the electrical connector: X5 @ A11 Radio
  3. Wait for greater than 5 s.
  4. Connect appropriate EL-52552 pinout tool to A11 Radio
  5. Ignition - On / Vehicle - In Service Mode
  6. Test for 7 to 11 V between the test points: Signal circuit terminal @ A11 Radio & Ground (component side)
    • If not between 7 and 11 V 

      Replace the component: A11 Radio

    • Go to next step: If between 7 and 11 V 
  7. Ignition/Vehicle & All vehicle systems - Off
  8. Disconnect the electrical connector: B87 Rearview Camera
  9. Locate the appropriate pinout adapter and load test loop adapter from EL-52552 COAX FAKRA Cable Adaptor Kit.
  10. Connect the 2 adapters together, measure and record the resistance between the terminals at the pinout adapter.
  11. Disconnect the 2 adapters and connect each one to the appropriate end of the coax cable.
  12. At the pinout adapter test terminals, measure the total resistance of the coax cable loop including the connected load test adapter.
    • If not within 5 Ω of the reading from step 10. 

      Replace the coax cable

    • Go to next step: If within 5 Ω of the reading from step 10. 
  13. Replace the component: B87 Rearview Camera
  14. Apply the parking brake.
  15. Engine Running Transmission in Reverse
  16. Verify DTC B127B is not set
    • If the DTC is set 

      Replace the component: A11 Radio

    • Go to next step: If the DTC is not set 
  17. All OK.
Factory Service Tools

Use the Manual With the Right Hardware

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

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote 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.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.