Chevrolet 1993 Astro Passenger Owner's Manual page 170

Brake
System
Warning Light
Standard Cluster Digital Cluster
PO641
This light
appears
on your
instrument
cluster to
warn you if your regular
braking system
needs
service.
See "Brake System Warning Light" in
the
Index.
Anti-lock
Brake
System Warning Light
Standard CIusfer Digital Cluster
This light appears on the instrument cluster to warn
you if
your
anti-lock
brake system needs service. See "Anti-lock Brake System Warning Light" in
the Index.
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