GMC 1994 Yukon Owner's Manual page 123

Waiting to do repairs can be costly
-
and even dangerous. So please get to
know your warning lights and gages. They're a big help.
Brake System Warning Light
The red brake system
warning light is
located at the bottom
right corner of the
instrument cluster
Your vehicle's hydraulic brake system is divided into two parts. If one part
isn't working, the other part can still work and stop you. For good braking,
though, you need both parts working well.
If the warning light comes on, there could be a brake problem. Have your
brake system inspected right away.
This light should come on as you start the vehicle. If it doesn't come on
then, have it fixed so it will be ready to warn you if there's a problem.
If the light comes on while you are driving, pull off the road and stop
carefully. You may notice that the pedal is harder to push. Or, the pedal may
go closer to the floor. It may take longer to stop. If the light is still on, have
the vehicle towed for service. (See "Towing Your Vehicle" in the Index.)
The brake system warning light will also come on when you set your
parking brake, and it will
stay on if your parking brake doesn't release fully.
If
it
stays on after your parking brake is fully released, it means you have a
brake problem.
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