2008 Hummer H3 Base, AutomaticFACTORY OEM SERVICE PROCEDURE

OnStar Button Assembly Replacement

WARNING: This page is about a different car, the 2008 Isuzu i-370, 2008 Isuzu i-290, 2008 GMC Canyon, and 2008 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: View Of OnStar Button Assembly
GM1334662Courtesy of GENERAL MOTORS CORP.

The OnStar ® button assembly located on the inside rearview mirror can not be serviced separately. Should the button assembly need to be replaced, the entire inside rearview mirror assembly will need to be replaced. Refer to Inside Rearview Mirror Replacement .

Factory Service Tools

Use the Manual With the Right Hardware

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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.