Checking Brake Fluid
You can check the brake fluid without taking off the cap.

Look at the brake fluid reservoir. The fluid level should be above MIN. If it is not, have your brake system checked to see if there is a leak.
After work is done on the brake hydraulic system, make sure the level is above the MIN, but not over the MAX mark.
See also:
Managing the Vehicle Damage Repair Process
In the event that the vehicle requires damage repairs, GM recommends that you
take an active role in its repair. If you have a pre-determined repair facility
of choice, take the vehicle there, or ...
Antilock Brake System (ABS) Warning Light
This light comes on briefly when the
engine is started.
If the light does not come on, have it
fixed so it will be ready to warn if
there is a problem.
If the ABS light stays on, turn the
...
Inadvertent Power Battery Saver
This feature is designed to protect your vehicle’s battery
against drainage from the interior lamps, or garage
door opener. When the ignition is turned off, the power
to these features will au ...
