GMC 1993 Safari Owner's Manual page 116

Features & Contmls
Warning lights go on when there may be or is a problem with one of your
vehicle's functions. As you will see in the details on the next few pages,
some warning lights come on briefly when you turn the ignition key just to let
you know they're working. If you are familiar with this section, you should not
be alarmed when this happens.
Gages can indicate when there may be or is a problem with one of your
vehicle's functions. Often gages and warning lights work together to let you
know when there's a problem with your vehicle.
When one of the warning lights comes on and stays on when you are
driving, or when one of the gages shows there may be a problem, check the
section that tells you what to do about it. Please follow the manual's advice.
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
Sfandard Cluster Digifal Cluster
8RAKE
-
PO641
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 goes 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.
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