Nokia RM-824 Service Manual

Contents

Display module troubleshootingGeneral instructions for display troubleshootingThe first step is to verify with a working display that the fault is not on the display module itself. The displaymodule cannot be repaired.Note: Always use the display with the phone's window while checking the display's visualfunctionality.After this, proceed to the display troubleshooting flowcharts.Pixel defectsTable 5 Display module troubleshooting casesDisplay blank There is no image on the display. The display looksthe same when the phone is on as it does when thephone is off.Image on the display not correct Image on the display can be corrupted or a part ofthe image can be missing. If a part of the image ismissing, change the display module. If the image isotherwise corrupted, follow the appropriatetroubleshooting diagram.Visual defects (pixel) The display may have some random pixel defectsthat are acceptable for this type of display. Thecriteria when pixel defects are regarded as a displayfailure, resulting in a replacement of the display, arepresented in the following table.Table 6 Pixel defectsBright sub-pixels (sometimes called on-pixels or stuck-on) arecharacterized by the appearance of bright/coloredpixels in, for example, black full screen picture.Dark sub-pixels (sometimes called off-pixels, stuck-off, or blackpixels) are characterized by the appearance of darkpixels in white, red, green, or blue full-screenpicture.RM-824; RM-825; RM-826BB Troubleshooting GuidePage 3 – 22 NOKIA INTERNAL USE ONLY Issue 2Copyright © 2012 Nokia. All rights reserved.