IBM THINKPAD 760C/CD (9546) - Manual (Page 605)

Check for the following conditions:
You should be able to vary the screen intensity by
adjusting the contrast and brightness controls.
The screen should be white or light gray, with a black
margin (test margin) on the screen.
Note: The location of the test margin varies with the
type of display. The test margin might be on
the top, bottom, or one or both sides.
If you do not see a test margin on the screen, replace the
display. If there is a test margin on the screen, replace the
system board.
Note: On ThinkPad Models 700, 700C, 720C, 720C, do
the following:
1. Video card
2. System board
External Keyboard/Auxiliary Input
Device Checkout
The following auxiliary input devices may be available for
IBM ThinkPad models.
– Numeric keypad
– Mouse (PS/2 compatible)
– External keyboard (with Keyboard/Miniature
Mouse cable)
If you suspect a problem with any of the auxiliary
input devices (listed above), replace the device.
If the problem is not corrected, replace the following
FRUs one at a time to correct the problem.
– Keyboard control card
– System board
If the computer receives an incorrect keyboard
response, remove other external devices, check the
keyboard connections, and recheck the keyboard
responses. If the problem remains, replace the
following FRUs one at a time to correct the problem.
–
Keyboard
– Keyboard control card
– System board
If a 00030100 error message appears, power-off the
computer and the external devices. Then power-on
the computer before you power-on the external
devices.
Common Devices Checkout 593