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Interpreting Diagnostic Lights
What the Lights
Mean
Diagnostic lights that remain on after system tests are complete
indicate an error. Table 5–4 lists some common errors indicated
by the diagnostic light patterns. In these patterns, X=on and
O=off.
Table 5–4 Diagnostic Light Patterns of Common Problems
Pattern
7654
3210
Meaning
OOXO OOOX
The LCSPX video RAM (random access
memory) test failed.
OOXO OXXO
The LCSPX virtual address test failed.
OOXX OXOX
The LK401 test failed.
OOXX OXXO
The mouse test failed.
OXOX OOOO
The memory byte mask test failed.
XOOX OOOX
The network address test failed.
XOOX XOXO
The loopback test failed.
XOXO OXOX
The SCSI minimal device test failed.
XOOX XOOX
The ThinWire terminator is not properly
connected.
Testing System Components 5–7