Page 23 - Electronic Mechanic - TP - Volume - 2

ELECTRONICS MECHANIC - CITS

EXERCISE 119: Dismantle the cell phone / smart phone

remove the keypad and clean it , test the

continuity of the matrix/tracks

Objectives

At the end of this exercise you shall be able to:
• remove key pad of the cell phone and clean it
• replace the display and keypad of the given cell phone
• remove touch screen of the smart phone and clean it.

Requirements

Tools/Materials
• Precision Screwdriver Set - 1 Set. • Replacement Parts - as reqd
• Tweezers - 1 Pair. • Magnifying Glass - 1 No.
• Plastic Opening Tools - 1 Set. • Smart Phone - 1 No.
• Heat Gun - 1 Set. • Digital Multimeter with probes - 1 No.
• Soldring Iron - 1 No. • User Manual of the given
• Desoldring Pump - 1 No. cell phone - 1 No.

Procedure

TASK 1: Remove the keypad and clean it

1 Dismantle the cell phone by referring the previous exercise.
2 Make a mixer of half rubbing alcohol and half distilled water.
3 Wipe the phones keypad with a soft cloth and remove dust.
4 Allow the cell phone to dry before reinserting the battery or putting it back in its case.

5 Check the continuity of row and column pins using DMM.
6 Place the key pad in the right position while closing the front cover for the reassembly. Do not assemble the
phone of display has to be replaced.

7 Switch ON the phone and check the working condition.

TASK 2: Replace the display
1 Dismantle the cell phone by referring the previous exercise.
2 Remove the display by removing the small star head screw and lift the LCD display out of the cell phone
3 Install the new display into your cell phone and follow the procedure in reverse order.

4 Insert the battery and battery cover. Switch ON the phone and check for its working.

TASK 3: Removing and cleaning the touch screen
1 Turn the device off.
2 Cover the whole screen with some clear packaging tape.

3 Remove the back cover.

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