Intermittent Problems; Undetermined Problems - Lenovo ThinkPad T430 Hardware Maintenance Manual

Notes:
• This policy applies to all ThinkPad notebook computers purchased on 1 January, 2008 or later.
• Lenovo will not provide warranty replacement if the LCD is within specifications because we cannot
guarantee that any replacement LCD will have zero pixel defects.
• One pixel consists of R, G, B sub-pixels.
Table 6. LCD-related symptoms
Symptom or error
No beep, power-on indicator on, and a blank LCD during
POST.
• LCD backlight not working.
• LCD too dark.
• LCD brightness cannot be adjusted.
• LCD contrast cannot be adjusted.
• LCD screen unreadable.
• Characters missing pixels.
• Screen abnormal.
• Wrong color displayed.
Horizontal or vertical lines displayed on LCD.

Intermittent problems

Intermittent system hang problems can be due to a variety of causes that have nothing to do with a hardware
defect, such as cosmic radiation, electrostatic discharge, or software errors. FRU replacement should be
considered only when a problem recurs.

Undetermined problems

If the diagnostic tests did not identify the device that has failed, if wrong devices are installed, or if the
system simply is not operating, follow these procedures to isolate the failing FRU (do not isolate FRUs
that have no defects).
Verify that all attached devices are supported by the computer.
Verify that the power supply being used at the time of the failure is operating correctly. (See "Power system
checkout" on page 32.)
1. Turn off the computer.
2. Visually check each FRU for damage. Replace any damaged FRU.
3. Remove or disconnect all of the following devices:
a. Non-ThinkPad devices
b. Devices attached to the docking station or the port replicator
c. Printer, mouse, and other external devices
d. Battery pack
e. Hard disk drive
f. External diskette drive or optical drive
g. Memory module in the slot on the underside of the computer (To locate the slot, See "1070 Memory
module (in the slot on the underside of the computer)" on page 75.)
h. Optical disk or diskette in the internal drive
i. Smart card, Expresscard, and media card
4. Turn on the computer.
5. Determine whether the problem has been solved.
FRU or action, in sequence
System board.
1. Reseat the LCD connectors.
2. LCD assembly.
3. System board.
1. See important note for "LCD-related symptoms."
2. Reseat all LCD connectors.
3. LCD assembly.
4. System board.
LCD assembly.
Chapter 4
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Related service information
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