Display module troubleshooting
General instructions for display troubleshooting
• The display is in a normal mode when the phone is in active use.
• Display is in a partial idle mode when the phone is in the screen saver mode.
• The operating modes of the display can be controlled with the help of
Image on the display not correct
Backlight dim or not working at all
Visual defects (pixel)
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Table 8 Display module troubleshooting cases
Table 9 Pixel defects
White dot defect
Two single dot defects that are within 5 mm of each other should be
interpreted as combined dot defect.
Copyright © 2007 Nokia. All rights reserved.
BB Troubleshooting and Tuning Guide
There is no image on the display. The display looks
the same when the phone is on as it does when the
phone is off. The backlight can be on in some cases.
Image on the display can be corrupted or a part of
the image can be missing. If a part of the image is
missing, change the display module. If the image is
otherwise corrupted, follow the appropriate
Backlight LED components are inside the display
module. Backlight failure can also be in the
connector or in the backlight power source in the
main engine of the phone.
This means that in case the display is working
(image OK), the backlight is faulty.
Pixel defects can be checked by controlling the
display with Phoenix. Use both colours, black and
white, on a full screen.
The display may have some random pixel defects
that are acceptable for this type of display. The
criteria when pixel defects are regarded as a display
failure, resulting in a replacement of the display, are
presented the following table.