Sun Microsystems SPARCstation 4 110 Service Manual page 45

Note – The Caps Lock key LED on some U.S. keyboards, located just above the left-
hand Shift key, is not used as a POST failure indicator, but blinks on and off while
POST is running.
If the Caps Lock key fails to flash on and off after you have pressed and held the
Stop-d keys when you power on the system, POST failed. See Section 4.2.2 "System
Board Test" on page 4-5, for troubleshooting information.
Chapter 3 Power-On Self-Test (POST) 3-9