See also:

Bulb Replacement
For the proper type of replacement bulbs, see Replacement Bulbs. For any bulb changing procedure not listed in this section, contact your dealer/retailer. ...

Cellular and GPS Antennas
Avoid placing items over or near the antenna to prevent blocking cellular and GPS signal reception. Cellular reception is required for OnStar to send remote signals to the vehicle. ...

How to Check Automatic Transmission Fluid (3.9L Engine)
Because this operation can be a little difficult, you may choose to have this done at the dealer/retailer service department. If you do it yourself, be sure to follow all the instructions here, ...