Display - Ericsson PF 768 Troubleshooting Instructions

PF768, Standard Electrical Repairs

5 Display.

5.1 Kind of fault.
Insert a charged battery into the phone and start it up by pressing the On/Off key.
• If it doesn't start, proceed to chapter 3 ("Doesn´t start"-fault).
• If the display is missing one or more segments, proceed to section 5.2.
• If there's nothing being displayed in the display or if the contrast is low, proceed
• If the display is black (all the segments are "lit" and you can sometimes make
5.2 Segments are missing.
Open the phone and check for liquid damages. Replace the display.
5.3
Insert a dummy battery into the phone, start it up and check the current consump-
tion. You could also disassemble the phone, place the board in the fixture, give the
board power, start it up by pressing the On/Off key or by pulling DCIO high and
check the current consumption.
• If the phone consumes more than 200mA, make sure the display isn't mechani-
• If the phone consumes less than 200mA, open the phone and check for liquid
Give the board power and start it up without the display mounted.
The component side of the circuit board is shown in fig. 5.1.
to section 5.3
out what it's displaying), proceed to section 5.4.
There's nothing showing in the display or
the contrast is low.
cally damaged.
* If the display is ok, replace the elastomer and try again.
* If that doesn't help, replace the display and try again.
* If the current consumption still is too high, proceed to chapter 3
("Doesn´t start"-fault).
damages.
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