Toshiba Satellite L450 L450d Pro Maintanance Manual

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
17 
2.5  Keyboard Troubleshooting 
P erform  external keybo ard check
(P rocedure 1)
STA RT
D oes the external
keyboard function ok?
P erform  diag nostic check (Procedure 2)
W as a keyboard
problem  detected?
P erform  con nector and replacem ent check
(Procedure 3)
R eplace system  board
END
Yes
No
K eyboard is not
fa u lty . C o n tin u e
troubleshooting-refer to Figure 2.1
No
Yes
 
 
Figure 2-4 Keyboard troubleshooting process  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
18 
To determine if the computer’s keyboard 
is functioning properly, perform the following 
procedures. Figure 2-4 outlines the process. Start with Procedure 1 and continue with the 
other procedures as instructed. 
Procedure 1:  External keyboard check 
Procedure 2:  Diagnostic check 
Procedure 3:  Connector and replacement check 
Procedure 1  External keyboard check 
Connect a USB keyboard to one of the computer’s USB ports, and then boot the computer. 
The computer automatically de tects the external keyboard. 
If the external keyboard works  correctly, the internal keyboard  or its connections may be 
faulty.  Go to Procedure 2. 
If the external keyboard appear s to have the same problem as the internal keyboard, the 
system board may be having some problem.   Replace it with a new one and following the 
instructions in Chapter 4. 
Procedure 2  Diagnostic check 
Run the 
test and Diagnostics Program, which will automatically execute the Keyboard Test.  
Refer to Chapter 3, 
Tests and Diagnostics  for more information on how to run the program. 
If an error is located, go to Procedure 3.   If an error does not occur, the keyboard is 
functioning ok. 
Procedure 3  Connector and replacement check 
The keyboard and/or system board may be di sconnected or damaged.  Disassemble the 
computer following the steps described in Chapter 4,  Replacement Procedures and perform 
the following checks. 
Check 1  Make sure the keyboard cable is firmly connected to the system board.  
If the connection is loose, reconnect firmly  and repeat Procedure 2. If there is still 
an error, go to Check 2. 
Check 2  The keyboard may be damaged. Replace it with a new one following the  instructions in Chapter 4. 
If the problem still exists, perform Check 3.  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
19 
Check 3  The system board may be damaged.  Replace it with a new one following the 
instructions in Chapter 4. 
 
2.6 External USB Devices Troubleshooting 
R eplace system  board
(P ro c e d u re  2 )
EN D
Original USB
d e v ic e  is  fa u lty
P e rfo rm  e x te rn a l d e v ic e  a n d connection check(P ro c e d u re  1 )
STA R T
D oes the device function w hen connected  to a
d iffe re n t U S B  p o rt?
D o e s  a n  a lte rn a tiv e  U S B
device function correctly?
No
Yes
No
Check USB
port
c o n n e c tio nYes
 
Figure 2-5 External USB d evice troubleshooting process  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
20 
 
To determine if the computer’s external US B devices are functioning properly, perform the 
following procedures. Figure 2-5 outlines the process.  Start with Procedure 1 and continue as   
instructed. 
Procedure 1:  External device and connection check 
Procedure 2:  Replace system board 
Procedure 1  External device and connection check 
The USB device may be damaged or the c onnection may be faulty. Perform Check 1. 
Check 1  Make sure USB device cable is firmly  plugged into one of the USB sockets. If the 
cable is connected correctly, go to Check 2. 
Check 2  Plug the USB device into another USB socket (there are three in all). If the USB  device still does not work, go to Check 4. 
If the device functions correctly when connected to another USB port, go to 
Check 3. 
Check 3  Make sure that the USB socket is firmly secured to the system board of the  computer. If the malfunction remains, the  system board or USB small board may 
be damaged. Go to Procedure 2. 
Check 4  Connect an alternative USB device to  one of the computer’s USB ports, and then 
boot the computer. The computer automa tically detects the external device. 
If the alternative USB device works correctly, the original device may be 
damaged and should be replaced. 
If the alternative USB device appears to  have the same problem as the original 
device, the system board or USB small board may be damaged. Go to Procedure 
2. 
Procedure 2  Replace system board 
If the error persists, the system board or USB small board may be damaged. Replace it with a 
new one following the instructions in Chapter 4. 
  
						

							2 Troubleshooting Procedures 
Satellite L450D/455D, Satellite pro L450D Series Maintenance Manual 
 
                                                                    
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2.7  Touchpad Troubleshooting  
START
END
TouchPad connection
check (Procedure 1)
TouchPad replacement check (Procedure 2)
Replace system board
 
Figure 2-6 Touchpad troubleshooting process  
						

							2 Troubleshooting Procedures 
Satellite L450D/455D, Satellite pro L450D Series Maintenance Manual 
 
                                                                    
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To determine if the computer’s built-in T
ouchPad is functioning properly, perform the 
following procedures. Figure 2-9 outlines the proce ss. Start with Procedure 1 and continue as 
instructed. 
Procedure 1:  TouchPad connection check 
Procedure 2:  TouchPad replacement check 
Procedure 1  TouchPad connection check 
The TouchPad is connected via the TouchPad  FPC to the system board. Make sure the 
TouchPad FPC cable is firmly connected to th e TouchPad and system board. Refer to Chapter 
4, Replacement Procedures,  for instructions on how to disassemble the computer and then 
perform the following checks. 
If any of the connections are loose, reconnect fi rmly.  If any of the connections is damaged, or 
there is still an erro r, go to Procedure 2. 
Procedure 2  TouchPad replacement check 
The TouchPad unit or FPC may be defective  or damaged.  Replace each with a new one 
following the steps in Chapter 4.  If the FPC  is still not functioning properly, replace the 
system board with a new one following the steps in Chapter 4. 
 
 
 
 
 
 
 
 
 
  
						

							2 Troubleshooting Procedures 
Satellite L450D/455D, Satellite pro L450D Series Maintenance Manual 
 
                                                                    
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2.8  Speaker Troubleshooting 
START
Do all sources have
same problem?
END
Perform earphone test
(Procedure 2)
Do earphones
function correctly?
Perform connection check
(Procedure 3)
Perform replacement check
(Procedure 4)
Perform audio source test
(Procedure 1)
/P
:FT
Yes
Replace system board
Speakers are notfaulty. Continue
troubleshooting -
see Figure 2-1
No
 
Figure 2-7 Speaker troubleshooting process  
To determine if the computer’s built-in sp eakers are functioning properly, perform the 
following procedures. Figure 2-7 outlines the process. First adjust the speaker volume to an 
appropriate level. Start with Procedure 1 and continue as instructed. 
  
						

							2 Troubleshooting Procedures 
Satellite L450D/455D, Satellite pro L450D Series Maintenance Manual 
 
                                                                    
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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 source devices. If all have the sa me problem, continue with Procedure 2. 
Procedure 2  Earphone test 
Connect a set if earphones or exte rnal speakers. If these function correctly, go to Procedure 3. 
If they do not function correctl y, 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 firm ly connected to the audio board. If the 
stereo speakers are still not functioning properly, go to Procedure 4. 
Procedure 4  Replacement check 
If the stereo speakers dont sound properly, the  stereo speakers may be defective or damaged. 
Replace them with new ones. If the stereo speakers still do not work properly, try replacing in 
turn the audio board and system board. 
 
 
  
						

							2 Troubleshooting Procedures 
Satellite L450D/455D, Satellite pro L450D Series Maintenance Manual 
 
                                                                    
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2.9   Optical drive troubleshooting 
START
Audio CD functions ok?
END
Perform software check (Procedure 3)
Perform diagnostic test(Procedure 4)
Perform connection and
replacement check(Procedure 5)
Perform audio CD check
(Procedure 1)
Perform drive-
cleaning check (Procedure 2)
No
Yes
Replace system board
 
Figure 2-8 Optical drive  troubleshooting process 
This section describes how to determine if the  computer’s internal optical drive is functioning 
properly. The  Satellite A350, SATEGO A350, EQUIUM  A350 Series Maintenance Manual 
module bays can accommodate the following optical drives:  
DVD SuperMulti supporting +-R Double Rayer  
						

							2 Troubleshooting Procedures 
Satellite L450D/455D, Satellite pro L450D Series Maintenance Manual 
 
                                                                    
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Figure 2-8 outlines the process. Perform the steps below starting with Procedure 1 and 
continue with the other procedures as required. 
 
Procedure 1:  Audio CD test 
Procedure 2:  Drive cleaning check 
Procedure 3:  Software check 
Procedure 4:  Diagnostic test 
Procedure 5:  Connection and replacement check 
Procedure 1  Audio CD check 
First, insert an audio CD into  the CD/DVD drive. If it works,  the problem is not with the 
drive. Go to Procedure 3. If the audio CD  does not work, go to Procedure 2. If the CD/DVD 
LED on the front panel does not light when the di sc is played and the drive gives no response, 
go straight to Procedure 3. 
Procedure 2  Drive cleaning check 
Insert a CD/DVD drive-cleaning disk into the  drive clean according to the drive-cleaning 
product instructions. If the problem  persists, go to Procedure 3. 
Procedure 3  Software check 
Ensure that the appropriate driver has been in stalled on the computer for the CD/DVD drive. 
Procedure 4  Diagnostic test 
The audio test program stored in  the Diagnostics Disk will test th e drive’s ability to play an 
audio CD. See Chapter 3 for details. 
If any errors occur while executing the diagnostic program, go to Procedure 5.