DEC DECstation 316+ Service Manual page 31

Troubleshooting 2–7
2. Run the Diagnose diagnostics.
3. Replace the necessary FRU.
2.5 Error Codes and Messages
During the power-up sequence, the DECstation executes built-in
diagnostic and bootstrap routines. During the first portion of
power up testing, the system generates beep codes on the speaker
if the test program detects a fatal error. The system uses the
beep codes to report test results only until screen initialization
and screen retrace verification have occurred. After screen
initialization and verification the built-in diagnostic sends non-
fatal error messages to video memory and the system displays the
messages on the monitor.
CAUTION
Do not connect or disconnect the video cable from the
monitor or system when the monitor or system, or both,
are on. This can cause damage to the system. Always
turn the monitor and system off, then wait 20 seconds and
disconnect the power cord before you remove the system
unit cover. Observe anti-static precautions.
2.5.1 Power Up Beep Codes
During the power up self test, the system generates two levels of
beep codes. The primary level consists of a combination of long
and short beeps which indicate possible system malfunction
conditions. The secondary level utilizes bursts of beeps in
a numeric beep code pattern to indicate specific malfunction
locations on the main logic board.
Table 2–2 lists the primary beep codes. The primary beep codes
indicate a main logic board failure, memory failure, memory
configuration error, or a video error. If a memory failure is
indicated, check and reseat the single-in-line memory modules
(SIMMs) on the 0K Memory Adapter. If you suspect a bad SIMM,
first replace one SIMM and then the other.