Toshiba Satellite L450 L450d Pro Maintanance Manual

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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If the diagnostics program cannot detect an erro
r, the problem may be intermittent.  The test 
program should be executed several times to isolate the problem.  When  a problem has been 
located, perform the appropriate trou bleshooting procedures as follows:  
1.  If an error is detected by  the battery test, perform th e Power Supply Troubleshooting 
procedures in Section 2.3 
2.  If an error is detected  by the display test, perform the Display Troubleshooting 
procedures in Section 2.4 
3.  If an error is detected by the keyboard test, perform the Keyboard Troubleshooting 
procedures in Section 2.5 
4.  If an error is detected  by the TouchPad test, perform the TouchPad Troubleshooting 
procedures in Section 2.7 
5.  If an error is detected  by the audio beep test, perform the Speaker Troubleshooting 
procedures in Section 2.8 and the Optic al Drive Troubleshooting Procedures in 
Section 2.9  
						

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Other problems that are not covered by the di
agnostics program may be discovered by a 
user. 
1.  If an error is detected when using an ex ternal USB device, perform the External USB 
Devices Troubleshooting procedures in Section 2.6 
2.  If an error is detected when using the  speakers, perform the Speaker Troubleshooting 
procedures in Section 2.8 
3.  If an error is detected when using th e modem, perform the Modem Troubleshooting 
procedures in Section 2.10 
4.  If an error is detected when using th e Wireless LAN, perform the Wireless LAN 
Troubleshooting procedures in Section 2.11 
5.  If an error is detected when using the HDMI TV, perform the HDMI TV 
troubleshooting procedures in Section 2.16. 
6.  If an error is detected when using the MIC, perform the MIC troubleshooting 
procedures in Section 2.17 
  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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2.3  Power Supply Troubleshooting 
START
Are the DC-IN and
B attery L E D s lit?
Can you turn the computer on?
A re the internal po w erconnections secure?
END
Check Power Supply Status (Procedure 1)
/P
:FT
Check power supplyconnections
(Procedure 3)
Run diagnostic program (Procedure 4):FT
/P
Replace adaptor / battery (Procedure 2)
/PP erform  internal co nnection check
(Procedure 5)
Replace system board
:FT
 
Figure 2-2 Power Supply Troubleshooting Process  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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The power supply controls many functions and 
components.  To determine if the power 
supply is functioning properly, star t with Procedure 1 and continue with the other Procedures 
as instructed. The flowchart in Figure 2-2 give s a summary of the process.  The procedures 
described in this section are: 
Procedure 1:  Power status check 
Procedure 2:  Adaptor / battery replacement 
Procedure 3:  Power supply connection check 
Procedure 4:  Diagnostic check 
Procedure 5:  Internal connection check 
 
Procedure 1  Power Status Check 
The following LEDS indicate  the power supply status: 
Battery LED 
DC-IN LED 
The power supply controller displays the power supply status through the Battery and the DC-
IN LEDS as listed in the tables below. 
Table 2-1 Battery LED 
Battery State  LED colors  Definition 
Red, solid on   Battery charging with AC. 
White, solid on  Battery fully charged by AC 
Charging 
Red color off  Battery abnormal stop charging with AC  (Bad cell/ Overheated) 
Red, blinking 
(LED on for 1 second 
every 4 seconds) Battery within low state: 12 minutes 
remaining 
Red, blinking 
(LED on for 1 second 
every 2 seconds) Battery within critical low state: 3 
minutes remaining. The system is 
protected and cannot 
be re-powered on 
without the AC power connected.  
Discharging 
Red color off  Battery not in low or critical low state;  It’s in discharging state 
  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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Table 2-2 DC-IN LED 
AC-IN LED  Power supply status 
Solid on  AC power exists (LED is solid White). 
Off  No AC power exists. 
 
To check the power supply status, install a ba ttery pack and connect an AC adaptor to the 
DC-IN port on the computer and to a power supply. 
If the DC-IN LED or Battery LED  is not lit, go to Procedure 2. 
 
Procedure 2  Adaptor / battery replacement 
A faulty adaptor may not supply power or ma y not charge the battery. Perform Check 1. 
Check 1  Connect a new AC adaptor. If the problem is not resolved, go to Check 2. 
Check 2  Insert a new battery. If the problem  is still not resolved, go to Procedure 3.  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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Procedure 3  Power supply connection check 
The power supply wiring diagram is shown below: 
AC
adaptorSyst em boardBattery
AC adaptor cord
AC p o we r  c o r d
 
Any of the connectors may be disconnected.  Perform Check 1. 
Check 1  Disconnect the AC power cord from  wall outlet. Check the power cable for 
breaks. If the power cord is damaged, c onnect a new AC power cord. If there is 
no damage, go to Check 2. 
Check 2  Make sure the AC adaptor cord and  AC power cord are firmly plugged into the 
DC-IN socket, AC adaptor inlet and wa ll outlet. If these cables are connected 
correctly, go to Check 3. 
Check 3  Make sure that the DC-IN input port so cket is firmly secured to the system board 
of the computer. 
  If the DC-IN input socket is loose, go to Procedure 5. 
  If it is not loose, go to Check 4. 
Check 4  Use a multi-meter to make sure that  the AC adaptor output voltage is close to 19 
V.  If the output is several percent lowe r than 19 V, go to Check 5.  If the output 
is close to 19 V, go to Check 6. 
Check 5  Connect a new AC adaptor or AC power cord.    If the DC-IN LED does not light, go to Procedure 4. 
  If the battery LED does not light, go to Check 6. 
Check 6  Make sure the battery pack is installed in the computer correctly.  If the battery is  properly installed and the battery LED still does not light, go to Procedure 4.   
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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Procedure 4  Diagnostic check 
The power supply may not charge the battery
 pack.  Perform the following procedures: 
1.  Reinstall the battery pack. 
2.  Attach the AC adaptor and turn on the power .  If you cannot turn on the power, go to 
Procedure 5. 
3.  Run the Diagnostic test following the proce dures described in Chapter 3, Tests and 
Diagnostics. If no problem is detecte d, the battery is functioning normally. 
Procedure 5  Replacement check 
The system board may be disconnected or da maged. Disassemble the computer following the 
steps described in Chapter 4,  Replacement Procedures. Check the connection between the AC 
adaptor and the system board. After ch ecking the connection, perform Check 1: 
Check 1  Use a multi-meter to make sure that  the fuses on the system board are not blown. 
If a fuse is not blown, go to Check 2.  If a fuse is blown, go to Check \
3. 
Check 2  Make sure that the battery cable is fi rmly connected to the system board. If it is 
connected firmly, go to Check 3. 
Check 3  The system board may be damaged.  Replace it with a new one following the  instructions in Chapter 4. 
  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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2.4  Display Troubleshooting 
Perform  external display check
(Procedure 1)
STA RT
D oes the external
display function ok?
Perform  diagnostic check (Procedure 2)
No
Was a display
problem  detected?
Perform  connector and replacem ent check (Procedure 3)
R eplace system  board
END
Yes
Yes
No
Display is not
faulty. Continue
troubleshooting-
refer to  F ig u re 2 .1
 
Figure 2-3 Display troubleshooting process  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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This section describes how to determine if the computer’s display is functioning properly.  
The process is outlined in Figure 2-3. Start wi
th Procedure 1 and continue with the other 
procedures as instructed. 
Procedure 1:  External display check 
Procedure 2:  Diagnostic check 
Procedure 3:  Connector and replacement check 
 
Procedure 1  External display check 
Connect an external display to the compute r’s external monitor port, and then boot the 
computer.  The computer automatica lly detects the external display.  
If the external display works correctly, the inte rnal LCD may be damaged. Go to Procedure 3. 
If the external monitor appears to have the same problem as the internal monitor, the system 
board may be damaged.  Go to Procedure 2.   
Procedure 2  Diagnostic check 
The Display Test program is stored on the comp uter’s Diagnostics disk.  This program checks 
the display controller on the sy stem board.  Insert the Diagnos tics disk in the computer’s 
floppy disk drive, turn on the computer and run the test.  Refer to Chapter 3,  Tests and 
Diagnostics for details. 
If an error is detected,  go to Procedure 3.  If an error is not detected, the di splay is functioning 
properly.  
						

							2 Troubleshooting Procedures 
 Satellite L450D/455D, Satellite pr o L450D Series Maintenance Manual 
  
                                                                       
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Procedure 3  Connector and replacement check 
The FL inverter board, LCD module, and system board are connected to the display circuits.  
Any of these components may be 
damaged.  Refer to Chapter 4, Replacement Procedures, for 
instructions on how to disassemble the com puter and then perform the following checks: 
Check 1  Make sure the DDR RAM module is s eated properly. Test display again. If the 
problem still exits, replace the DDR RAM module. If the problem still exists, 
perform Check 2. 
Check 2  Replace the FL inverter board with  a new one and test display again.  If the 
problem still exists, perform Check 3. 
Check 3  Replace the LCD module with a new one and test display again.  If the problem  still exists, perform Check 4. 
Check 4  Replace the LCD/FL cable with a new one  and test display again.  If the problem 
still exists, perform Check 5. 
Check 5  Replace the CPU with another of the  same specifications.  If the problem still 
exists, perform Check 6. 
Check 6  The system board may be damaged.  Replace it with a new one.