Sony ST26i User manual

1268-3899 Rev 3
 Sony Mobile Communications AB – Company Internal
Troubleshooting Guide
- mechanical -
ST26i, ST26a

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
2(44)
CONTENTS
1 Problem Areas................................................................................4
1.1 Power....................................................................................................4
1.1.1 Will not power on or will switch off randomly...........................................4
1.2 Keys ......................................................................................................5
1.2.1 Menu/Home/Back Keys...............................................................................5
1.2.2 Volume Key..................................................................................................5
1.2.3 On/Off Key....................................................................................................6
1.3 Touch Screen .......................................................................................8
1.3.1 Touch Screen malfunction..........................................................................8
1.4 Display..................................................................................................9
1.4.1 Graphics & Illumination ..............................................................................9
1.5 LED/Illumination.................................................................................10
1.5.1 LED/Illumination........................................................................................10
1.5.2 Menu/Home/Back Keys Illumination........................................................11
1.6 Speaker...............................................................................................13
1.6.1 Speaker.......................................................................................................13
1.7 Earphone ............................................................................................16
1.7.1 Earphone....................................................................................................16
1.8 Microphone.........................................................................................17
1.8.1 Microphone................................................................................................17
1.9 Vibrator...............................................................................................19
1.9.1 Vibrator not generating alerts ..................................................................19
1.10 Camera................................................................................................20
1.10.1 Camera defects..........................................................................................20
1.10.2 Video Call Camera defects........................................................................21
1.11 Flash LED ...........................................................................................22
1.11.1 Flash LED not flashing..............................................................................22
1.12 Bluetooth and WLAN .........................................................................24
1.12.1 Bluetooth or WLAN connection failure....................................................24
1.13 GPS .....................................................................................................25
1.13.1 GPS malfunctions......................................................................................25
1.14 Compass.............................................................................................26
1.14.1 Compass fails............................................................................................26
1.15 Accelerometer....................................................................................27
1.15.1 Accelerometer test fails............................................................................27
1.16 Proximity Switch................................................................................28
1.16.1 Proximity switch malfunctions.................................................................28
1.17 Real Time Clock .................................................................................29
1.17.1 Real Time Clock test fails .........................................................................29
1.18 Total call time.....................................................................................30
1.18.1 Total call time fails ....................................................................................30
1.19 External Memory................................................................................31

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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1.19.1 Memory Card not detected .......................................................................31
1.20 Security...............................................................................................32
1.20.1 Security fails..............................................................................................32
1.21 FM Radio.............................................................................................33
1.21.1 No/Poor FM Radio reception ....................................................................33
1.22 Verify Certificates...............................................................................34
1.22.1 Verify certificates fails...............................................................................34
1.23 Network & Signal................................................................................35
1.23.1 No/Poor signal...........................................................................................35
1.24 SIM ......................................................................................................38
1.24.1 SIM not detected........................................................................................38
1.24.2 Incorrect SIM-Card adapter.......................................................................39
1.24.3 Incorrect SIM indicated.............................................................................39
1.25 Charging.............................................................................................40
1.25.1 Battery will not charge..............................................................................40
1.26 HandsFree by Wire.............................................................................42
1.26.1 Connection to Portable HandsFree fails..................................................42
1.27 Data Communication .........................................................................43
1.27.1 Data transfer via System Connector fails................................................43
2 Revision History...........................................................................44

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
4(44)
1 Problem Areas
1.1 Power
1.1.1 Will not power on or will switch
off randomly
Check:
Check whether the phone vibrates by pressing the on/off
key.
Action:
If activation of the vibrator is detected, refer to section 1.4
‘Display’.
Check:
Inspect the contact pads on the battery.
Action:
1. If dirty or oxidized – clean the pads.
2. If damaged – replace the battery.
Check:
Inspect the battery contact pins.
Action:
1. If dirty or oxidized – clean the contact pins.
2. If adhesive is detected on the contact pins, use an eraser
to gently rub off the adhesive.
3. If damaged – replace board.
Check:
Inspect the on/off key.
Action:
1. Refer to section 1.2.3 ‘Key On/Off’.
2. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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Problem Areas
1.2 Keys
1.2.1 Menu/Home/Back Keys
Check:
Inspect the Menu/Home/Back keys on the Front Cover
Display Assembly.
Action:
1. Refer to the section 1.3 ‘Touch Screen’.
2. Replace board.
1.2.2 Volume Key
Check:
Inspect the external area of the volume key.
Action:
If dirty – clean it.
Check:
Inspect the volume key (a) and the volume key push switch
(b).
Action:
1. If dirty – clean them.
2. If the volume key is damaged – replace the Side Key.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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Problem Areas: Keys
Check:
Inspect the BtB connector of the SIM SD Side Key FPC to
the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the BtB connector or the volume key push switch is
damaged – replace the SIM SD Side Key FPC.
4. Replace board.
1.2.3 On/Off Key
Check:
Inspect the external area of the on/off key.
Action:
If dirty – clean it.
Check:
Inspect the on/off key (a) and the on/off key push switch (b).
Action:
1. If dirty – clean them.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
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Problem Areas: Keys
2. If the on/off key is damaged – replace the Side Key.
Check:
Inspect the BtB connector of the SIM SD Side Key FPC to
the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the BtB connector or the on/off key push switch is
damaged – replace the SIM SD Side Key FPC.
4. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
8(44)
Problem Areas
1.3 Touch Screen
1.3.1 Touch Screen malfunction
Check:
Inspect the touch screen on the Front Cover Display
Assembly.
Action:
If dirty – clean it.
If: The end user has complained about unexpected behavior of the
touch screen or the touch keys.
Action: Calibrate the Touch Panel 1270-6729 Trouble Shooting
Application – mechanical.
Check:
Inspect the ZIF connector of the Front Cover Display
Assembly to the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
Check:
Inspect the ZIF connector of the touch panel FPC to the
display FPC.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the touch screen or the FPC of the Front Cover Display
Assembly is damaged – replace the Front Cover Display
Assembly.
4. Replace board.
Note: Calibrate the Touch Panel 1270-6729 Trouble Shooting
Application – mechanical after replacements of action 3
or action 4.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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Problem Areas
1.4 Display
1.4.1 Graphics & Illumination
Check:
Check whether the phone vibrates after the on/off key has
been pressed.
Action:
If the activation described above is not detected, refer to
section 1.1 ‘Power’.
Check:
Inspect the ZIF connector of the Front Cover Display
Assembly to the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the display or the FPC of the Front Cover Display
Assembly is damaged – replace the Front Cover Display
Assembly.
4. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
10(44)
Problem Areas
1.5 LED/Illumination
1.5.1 LED/Illumination
Check:
Inspect the external window area of the RGB LED on the
Front Cover Display Assembly.
Action:
1. If dirty – clean it.
2. If the external window area is damaged – replace the
Front Cover Display Assembly.
Check:
Inspect the RGB LED on the main PBA and the Proximity
rubber on the Front Cover Display Assembly.
Action:
1. If dirty or clogged – clean them.
2. If the Proximity rubber is damaged – replace it.
3. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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Problem Areas: Illumination
1.5.2 Menu/Home/Back Keys
Illumination
Check:
Inspect the illumination window of the Menu/Home/Back
keys on the Front Cover Display Assembly.
Action:
1. If dirty – clean them.
2. If the illumination window is damaged – replace the Front
Cover Display Assembly.
Check:
Inspect the ZIF connector of the Link FPC to the Sub Board
Assembly.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
Check:
Inspect the LEDs on the Sub Board Assembly.
Action:
1. If dirty– clean them.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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Problem Areas: Illumination
2. If the ZIF connector or the LEDs of the Sub Board
Assembly is damaged – replace the Sub Board Assembly.
Check:
Inspect the ZIF connector of the Link FPC to the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
2. If the Link FPC is damaged – replace it.
3. Replace Board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
13(44)
Problem Areas
1.6 Speaker
1.6.1 Speaker
Check:
Inspect the Loudspeaker’s external port on the Battery
Cover.
Action:
1. If the Loudspeaker external port is clogged – clean it.
2. If the Loudspeaker external port is damaged – replace the
Battery Cover.
Check:
Inspect the mesh of the Loudspeaker on the Rear Cover.
Action:
1. If dirty – clean it.
2. If the mesh is damaged – replace the Rear Cover.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
14(44)
Problem Areas: Speaker
Check:
Inspect the Loudspeaker’s pins and the pads on the Sub
Board Assembly.
Action:
1. If dirty – clean them.
2. If the pins of the Loudspeaker are damaged – replace the
Loudspeaker.
Check:
Inspect the ZIF connector of the Link FPC to the Sub Board
Assembly.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the pads or the ZIF connector of the Sub Board
Assembly is damaged – replace the Sub Board Assembly.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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Problem Areas: Speaker
Check:
Inspect the ZIF connector of the Link FPC to the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the ZIF connector or the FPC of the Link FPC is
damaged – replace the Link FPC.
4. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
16(44)
Problem Areas
1.7 Earphone
1.7.1 Earphone
Check:
Inspect the Receiver’s external port on the Front Cover
Display Assembly.
Action:
1. If clogged – clean it.
2. If the port is damaged – replace the Front Cover Display
Assembly.
Check:
Inspect the Receiver’s pins and the contact pins on the main
PBA.
Action:
1. If dirty – clean them.
2. If the pins of the Receiver are damaged – replace the
Receiver.
3. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
17(44)
Problem Areas
1.8 Microphone
1.8.1 Microphone
Check:
Inspect the Microphone’s external port on the Front Cover
Display Assembly.
Action:
If clogged – clean the port.
Check:
Inspect the microphone on the Sub Board Assembly and the
rubber on the Front Cover Display Assembly.
Action:
1. If dirty – clean them.
2. If the external port or the rubber is damaged – replace the
Front Cover Display Assembly.
Check:
Inspect the ZIF connector of the Link FPC to the Sub Board
Assembly.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
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Problem Areas: Microphone
3. If the microphone or the ZIF connector of the Sub Board
Assembly is damaged – replace the Sub Board Assembly.
Check:
Inspect the ZIF connector of the Link FPC to the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the ZIF connector or the FPC of the Link FPC is
damaged – replace the Link FPC.
4. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
19(44)
Problem Areas
1.9 Vibrator
1.9.1 Vibrator not generating alerts
Check:
Inspect the ZIF connector of the Link FPC to the Sub Board
Assembly.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the vibrator or the ZIF connector on the Sub Board
Assembly is damaged – replace the Sub Board Assembly.
Check:
Inspect the ZIF connector of the Link FPC to the main PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
3. If the ZIF connector or the FPC of the Link FPC is
damaged – replace the Link FPC.
4. Replace board.

Troubleshooting Guide (mech)
1268-3899 Rev 3
 Sony Mobile Communications AB –
Company Internal
20(44)
Problem Areas
1.10 Camera
1.10.1 Camera defects
Check:
Inspect the external area of camera window.
Action:
1. If dirty – clean it.
2. If the camera window scratched or damaged – replace the
Rear Cover.
Check:
Inspect the BtB connector of the Main Camera to the main
PBA.
Action:
1. If not properly connected – disconnect and reconnect.
2. If dirty or oxidized – clean it.
Check:
Inspect the Main Camera.
Action:
1. If the Main Camera is damaged – replace it.
2. Replace board.