2008 Hummer H3 Base, AutomaticFACTORY OEM SERVICE PROCEDURE

Circuit/System Verification

WARNING: This page is about a different car, the 2009 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition ON, verify the scan tool can communicate with right side object sensor.
    • If the scan tool can not communicate with the right side object sensor, refer to Circuit/System Testing , under Right Side Object Sensor Malfunction
  2. Verify the scan tool can communicate with left side object sensor.
    • If the scan tool can not communicate with the left side object sensor, refer to Circuit/System Testing , under Left Side Object Sensor Malfunction
  3. Ignition ON, verify that the side blind zone alert system indicators located in the outside rearview mirrors briefly turn ON and then turn OFF during the system self test.
    • If both indicators do not briefly illuminate during the system self test, the side blind zone alert system has been disabled. Refer to Diagnostic Aids.
    • If only one indicator does not briefly illuminate during the self test, refer toCircuit/System Testing , under Side Object Indicator Malfunction.
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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.