Toshiba Satellite L850D, Maintenance Manual

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2.4 System Board 2 Troubleshooting
Satellite/Satellite Pro/C850D/C855D/L850D/L855D Maintenance Manual 2-9
2.4 System Board
To check if the system board is defective or malfunctioning, follow the troubleshooting
procedures below as instructed.
Procedure 1 Message Check
Procedure 2 Test Program Check
Procedure 3 Replacement Check
Procedure 1 Message Check
When the power is turned on, the system performs the self-diagnostic Power On Self Test
(POST) embedded in the BIOS ROM. The POST tests and initializes each IC on the system
board.
If an error message appears on the display, perform Check 1.
If there is no error message, go to Procedure 2.
If FREE-DOS or Windows 7 is loaded normally, go to Procedure 3.
Check 1 If the following error message is displayed on the screen, press the
F1
key
as prompted. These errors occur when the system configuration preserved
in the RTC memory (generally called CMOS memory) does not match the
actual configuration or when the data is lost.
If you press the
F1
key as prompted by the message, the TSETUP screen
appears to set the system configuration. If the error message appears
frequently when the power is turned on, replace the RTC battery. If any
other error message is displayed, perform Check 2.
*** Bad RTC battery ***
Check system. Then press [F1] key
Check 2 If the following error message is displayed on the screen, press any key as
prompted by the message.
The error message appears when either data stored in RAM to be resumed
is lost because the battery has been exhausted or the system board is faulty.
*** Resume failure and press any key to continue ***