See also:

Warranty
OnStar equipment may be warranted as part of the new-vehicle limited warranty. The manufacturer of the vehicle furnishes detailed warranty information. ...

When to Check Power Steering Fluid
The power steering fluid does not need to be checked unless there is a leak in the system or you hear an unusual noise. Have the system inspected and repaired if there is a fluid loss. ...

Footnotes — Maintenance Schedule Additional Required Services — Normal
a) Check all fuel and vapor lines and hoses for proper hook-up, routing, and condition. Check that the purge valve, if the vehicle has one, works properly. Replace as needed. b) Or every four years, ...