Toshiba mini NB300, Руководство по обслуживанию

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2 Troubleshooting Procedures
NB300/305 Series Maintenance Manual
24
To determine if the computer’s built-in speakers are functioning properly, perform the
following procedures. Figure 2-10 outlines the process. First adjust the speaker volume to an
appropriate level. Start with Procedure 1 and continue as instructed.
Procedure 1: Audio source test
Procedure 2: Earphone test
Procedure 3: Connection check
Procedure 4: Replacement check
Procedure 1 Audio source test
Try different audio sources (e.g. an audio CD and digital music file) to determine whether the
fault is in the speaker system or not. If not all sources have sound problem, the problem is in
the monaural devices. If all have the same problem, continue with Procedure 2.
Procedure 2 Earphone test
Connect a set if earphones or external speakers. If these function correctly, go to Procedure 3.
If they do not function correctly, the system board may be defective or damaged. Replace it
with a new one.
Procedure 3 Connection check
Disassemble the computer following the steps described in Chapter 4, Replacement
Procedures and make sure the speaker cable is firmly connected to the audio board. If the
speakers are still not functioning properly, go to Procedure 4.
Procedure 4 Replacement check
If the monaural speakers don't sound properly, the monaural speakers may be defective or
damaged. Replace them with new ones. If the monaural speakers still do not work properly,
try replacing in turn the audio board and system board.