3-4 Diagnostic Tools

Power-On Self-Test (POST)
POST is a series of diagnostic tests that run automatically on Compaq computers when the
system is turned on. POST checks the following assemblies to ensure that the computer system
is functioning properly:
Processors
Keyboard
Power supply
System board
Memory
Memory expansion boards
Controllers
Diskette drives
Hard drives
If POST finds an error in the system, an audible and/or visual message appears. If an error
code appears on the screen during POST or after resetting the system, follow the instructions in
Table 3-1. Error messages and codes listed in Table 3-1 include all codes generated by
Compaq products. Your system generates only those codes that are applicable to your
configuration.
The Action column lists the steps needed to correct the problem. After completing each step,
run the Diagnostics program. If the error code reappears, perform the next step, then run the
Diagnostics program again. Repeat this procedure until the error is corrected.

Table 3-1

POST Error Messages

Error Code Audible
Beeps
L=Long
S=Short
Probable Source of
Problem Action
A Critical Error
occurred prior to
this power-up
None A catastrophic system
error, which caused the
server to crash, has been
logged.
Run Diagnostics. Replace failed
assembly as indicated.
101-ROM Error 1L,1S System ROM checksum. Run Diagnostics. Replace failed
assembly as indicated.
101-I/O ROM
Error
None Options ROM checksum. Run Diagnostics. Replace failed
assembly as indicated.
102-System
Board Failure
None DMA, timers, etc. Replace the system board. Run
the Compaq System
Configuration Utility.