
Troubleshooting Guide
- mechanical -
Xperia
LT39t
1279-7185 Rev 1
Sony Mobile Communications AB – Company Internal
TM
Z1

Troubleshooting Guide (mech)
CONTENTS
1 Problem Areas ................................................................................ 5
1.1 Power .................................................................................................... 5
1.1.1 Will not power on or will switch off randomly ........................................... 5
1.2 Keys ...................................................................................................... 7
1.2.1 Back, Menu, Home and Multitask Keys ..................................................... 7
1.2.2 Volume Key .................................................................................................. 7
1.2.3 On/Off Key .................................................................................................... 8
1.2.4 Camera Key ................................................................................................ 10
1.3 Touch Screen ..................................................................................... 12
1.3.1 Touch Screen malfunction ........................................................................ 12
1.4 Display ................................................................................................ 13
1.4.1 Graphics & Illumination ............................................................................ 13
1.5 LED/Illumination ................................................................................. 14
1.5.1 LED/Illumination ........................................................................................ 14
1.6 Speaker ............................................................................................... 15
1.6.1 Loudspeaker .............................................................................................. 15
1.7 Earphone ............................................................................................ 17
1.7.1 Ear Speaker ................................................................................................ 17
1.8 Microphone ......................................................................................... 18
1.8.1 Primary Microphone .................................................................................. 18
1.8.2 Secondary Microphone ............................................................................. 19
1.9 Vibrator ............................................................................................... 22
1.9.1 Vibrator not generating alerts .................................................................. 22
1.10 Camera ................................................................................................ 24
1.10.1 Main Camera .............................................................................................. 24
1.10.2 Video Call Camera defects ........................................................................ 25
1.11 Flash LED ........................................................................................... 26
1.11.1 Flash LED not flashing .............................................................................. 26
1.12 Bluetooth and WLAN ......................................................................... 28
1.12.1 Bluetooth or WLAN connection failure .................................................... 28
1.13 NFC ..................................................................................................... 29
1.13.1 NFC malfunctions ...................................................................................... 29
1.14 GPS ..................................................................................................... 30
1.14.1 GPS malfunctions ...................................................................................... 30
1.15 Compass ............................................................................................. 31
1.15.1 Compass fails ............................................................................................ 31
1.16 Accelerometer .................................................................................... 32
1.16.1 Accelerometer test fails ............................................................................ 32
1.17 Gyroscope .......................................................................................... 33
1.17.1 Gyroscope test fails .................................................................................. 33
1.18 Ambient Light Sensor ........................................................................ 34
1.18.1 Light Sensor malfunctions ....................................................................... 34
1279-7185 Rev 1
Sony Mobile Communications AB –
2(68)

Troubleshooting Guide (mech)
1.19 Proximity Switch ................................................................................ 36
1.19.1 Proximity switch malfunctions ................................................................. 36
1.20 Pressure Sensor ................................................................................. 38
1.20.1 Pressure Sensor test fails ......................................................................... 38
1.21 Water Resistance ............................................................................... 39
1.21.1 Water Resistance fails............................................................................... 39
1.22 Real Time Clock ................................................................................. 45
1.22.1 Real time clock test fails ........................................................................... 45
1.23 Total call time ..................................................................................... 46
1.23.1 Total call time fails .................................................................................... 46
1.24 External ............................................................................................... 47
1.24.1 Memory Card not detected ....................................................................... 47
1.25 Security ............................................................................................... 48
1.25.1 Security fails .............................................................................................. 48
1.26 FM Radio ............................................................................................. 49
1.26.1 No/Poor FM Radio reception .................................................................... 49
1.27 Battery Health test ............................................................................. 50
1.27.1 Battery Health test fails ............................................................................. 50
1.28 Flip Slider Counter ............................................................................. 51
1.28.1 Flip Slider Counter fails ............................................................................ 51
1.29 Verify Certificates ............................................................................... 52
1.29.1 Verify Certificates fails .............................................................................. 52
1.30 IrDA Test ............................................................................................. 53
1.30.1 IrDA test fails ............................................................................................. 53
1.31 TV-Out Test ......................................................................................... 54
1.31.1 TV-Out test fails ......................................................................................... 54
1.32 Network & Signal ................................................................................ 55
1.32.1 No/Poor signal ........................................................................................... 55
1.33 SIM ...................................................................................................... 62
1.33.1 SIM not detected ........................................................................................ 62
1.33.2 Incorrect UIM or SIM indicated ................................................................. 62
1.34 Charging ............................................................................................. 63
1.34.1 Battery will not charge by USB connector .............................................. 63
1.34.2 Battery will not charge by charge pad ..................................................... 63
1.35 HandsFree by Wire ............................................................................. 66
1.35.1 Connection to portable Handsfree fails ................................................... 66
1.36 Data Communication ......................................................................... 67
1.36.1 Data transfer via System Connector fails ................................................ 67
2 Revision History ........................................................................... 68
1279-7185 Rev 1
Sony Mobile Communications AB –
3(68)

Troubleshooting Guide (mech)
Always firstly disconnect the Battery FPC BtB connector to cut off power supply when the Sub
Antenna Assy is disassembled.
Always finally connect the Battery FPC BtB connector before the Sub Antenna Assy is
reassembled.
1279-7185 Rev 1
Sony Mobile Communications AB –
4(68)

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:
1. If activation of the vibrator is detected, refer to section 1.4
‘Display’.
Troubleshooting Guide (mech)
2. If NO activation of the Vibrator is detected, check that the
battery is charging when connected to a charger.
Follow 1279-7188 Test Instruction - mechanical chapter
2.3.7 (Charging via USB and Easy Charger), Diagnostic
Battery / Charging status.
Check:
Inspect the on/off key.
Action:
Refer to section 1.2.3 ‘On/Off Key’.
Check:
Inspect the BtB connector of the Battery to Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean the both sides of the BtB
connector.
1279-7185 Rev 1
Sony Mobile Communications AB –
5(68)

Problem Areas: Power
3. If the BtB connector, the Battery FPC or the Battery is damaged
– replace the Battery.
4. Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
6(68)

Problem Areas
1.2 Keys
1.2.1 Back, Menu, Home and
Multitask Keys
Action:
1. Refer to section 1.3 ‘Touch Screen’.
2. Replace Main PBA.
1.2.2 Volume Key
Check:
Inspect the external area of the Key Volume.
Action:
If dirty – clean it.
Troubleshooting Guide (mech)
Check:
Inspect the BtB connector of FPC Assy Relay/Side Key to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the FPC of FPC Assy Relay/Side Key is damaged –
replace the FPC Assy Relay/Side Key.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
7(68)

Problem Areas: Keys
Check:
Inspect the rubber of the Volume Key (a) and Volume Key
switch (b).
Action:
1. If dirty – clean them.
Troubleshooting Guide (mech)
2. If the rubber of the Volume Key is damaged – replace the
Display Frame Assy.
3. If the volume key switch is damaged – replace the FPC
Assy Relay/Side Key.
1.2.3 On/Off Key
Check:
Inspect the external area of the Power Key.
Action:
If dirty – clean it.
1279-7185 Rev 1
Sony Mobile Communications AB –
8(68)

Problem Areas: Keys
Check:
Inspect the BtB connector of FPC Assy Relay/Side Key to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the FPC of FPC Assy Relay/Side Key is damaged –
replace the FPC Assy Relay/Side Key.
4. Replace Main PBA.
Troubleshooting Guide (mech)
Check:
Inspect the rubber of the Power Key (a) and Power Key
switch (b).
Action:
1. If dirty – clean them.
2. If the rubber of the power key is damaged – replace the
Display Frame Assy.
1279-7185 Rev 1
Sony Mobile Communications AB –
9(68)

Problem Areas: Keys
3. If the power key switch is damaged – replace the FPC
Assy Relay/Side Key.
1.2.4 Camera Key
Check:
Inspect the external area of the Camera Key.
Action:
If dirty – clean it.
Troubleshooting Guide (mech)
Check:
Inspect the BtB connector of FPC Assy Relay/Side Key to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the FPC of FPC Assy Relay/Side Key is damaged –
replace the FPC Assy Relay/Side Key.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
10(68)

Problem Areas: Keys
Check:
Inspect the rubber of the Camera Key (a) and Camera Key
switch (b).
Action:
1. If dirty – clean them.
Troubleshooting Guide (mech)
2. If the rubber of the Camera Key is damaged – replace the
Display Frame Assy.
2. If the camera key switch is damaged – replace the FPC
Assy Relay/Side Key.
1279-7185 Rev 1
Sony Mobile Communications AB –
11(68)

Problem Areas
1.3 Touch Screen
1.3.1 Touch Screen malfunction
Check:
Inspect the touch screen of the Display Frame Assy.
Action:
1. If dirty – clean it.
Troubleshooting Guide (mech)
2. If scratched or damaged – replace the Display Frame
Assy.
Check:
Inspect the BtB connector of Display Frame Assy FPC to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the BtB connector of Display Frame Assy FPC or FPC
is damaged – replace the Display Frame Assy.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
12(68)

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 BtB connector of Display Frame Assy FPC to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the BtB connector of Display Frame Assy FPC or FPC
is damaged – replace the Display Frame Assy.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
13(68)

Problem Areas
1.5 LED/Illumination
1.5.1 LED/Illumination
Check:
Inspect external port of LED on the Display Frame Assy.
Action:
1. If dirty – clean it.
Check:
Inspect the BtB connector of FPC Assy Audio Jack to Main
PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the BtB connector of FPC Assy Audio Jack or FPC is
damaged – replace the FPC Assy Audio Jack.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
14(68)

Problem Areas
1.6 Speaker
1.6.1 Loudspeaker
Check:
Inspect the Speaker Panel on the Display Frame Assy.
Action:
1. If the Speaker Panel is clogged – clean it.
Troubleshooting Guide (mech)
2. If the Speaker Panel is damaged – replace the Speaker
Panel.
Check:
Inspect the contact pads of Loudspeaker and the contact
pads on the FPC Assy Relay/Side Key.
Action:
1. If dirty – clean them.
2. If the contact pads of Loudspeaker or the Loudspeaker
are damaged – replace the Main Antenna Speaker Sub
Assy.
1279-7185 Rev 1
Sony Mobile Communications AB –
15(68)

Problem Areas: Speaker
3. If the contact pads of FPC Assy Relay/Side Key are
damaged - replace the FPC Assy Relay/Side Key.
Check:
Inspect the BtB connector of FPC Assy Relay/Side Key to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the BtB connector of FPC Assy Relay/Side Key or FPC
is damaged – replace the FPC Assy Relay/Side Key.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
16(68)

Problem Areas
1.7 Earphone
1.7.1 Ear Speaker
Check:
Inspect the external port of Ear Speaker on the Display
Frame Assy.
Action:
1. If clogged – clean it.
Check:
Inspect the contact pads of Ear Speaker and the Ear
Speaker Conductive Films on the Main PBA.
Action:
1. If dirty – clean them.
Troubleshooting Guide (mech)
2. If the contact pads of the Ear Speaker or the Ear Speaker
are damaged – replace the Ear Speaker.
3. If Conductive Film Ear Speaker is damaged – replace
Conductive Film Ear Speaker.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
17(68)

Problem Areas
1.8 Microphone
1.8.1 Primary Microphone
Check:
Inspect the Speaker Panel on the Display Frame Assy.
Action:
1. If clogged – clean it.
Troubleshooting Guide (mech)
2. If the Speaker Panel is damaged – replace the Speaker
Panel.
Check:
Inspect the microphone on the FPC Assy Relay/Side Key.
Action:
1. If clogged – clean it.
2. If the microphone is damaged – replace the FPC Assy
Relay/Side Key.
Check:
Inspect the 1st Mic Cushion on Display Frame Assy.
Action:
1. If dirty – clean them.
1279-7185 Rev 1
Sony Mobile Communications AB –
18(68)

Problem Areas: Microphone
2. If the 1st Mic Cushion is damaged – replace Display
Frame Assy.
Check:
Inspect the BtB connector of FPC Assy Relay/Side Key to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the BtB connector of FPC Assy Relay/Side Key or FPC
is damaged – replace the FPC Assy Relay/Side Key.
4. Replace Main PBA.
1.8.2 Secondary Microphone
Check:
Inspect the external port of secondary microphone on the
Window Back Sub Assy.
Action:
1. If clogged – clean it.
1279-7185 Rev 1
Sony Mobile Communications AB –
19(68)

Problem Areas: Microphone
Check:
Inspect the Sheet WP 2nd Mic on the Window Back Sub
Assy.
Action:
1. If dirty – clean them.
Troubleshooting Guide (mech)
2. If the Sheet WP 2nd Mic is damaged – replace the
Window Back Sub Assy.
Check:
Inspect the Holder FPC Assy Audio Jack.
Action:
1. If the Holder FPC Assy Audio Jack is damaged – replace
it.
Check:
Inspect the Gasket 2nd MIC on the main PBA.
Action:
1. If the Gasket 2nd MIC is damaged – replace it.
1279-7185 Rev 1
Sony Mobile Communications AB –
20(68)

Problem Areas: Microphone
2. Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
21(68)

Problem Areas
1.9 Vibrator
1.9.1 Vibrator not generating alerts
Check:
Inspect the BtB connector of Vibrator to Display Frame Assy
FPC.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the connector or cables of vibrator or vibrator itself is
damaged – replace the Vibrator.
4. If the connector of vibrator on Display Frame Assy FPC is
damaged – replace the Display Frame Assy.
Check:
Inspect the BtB connector of Display Frame Assy FPC to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
1279-7185 Rev 1
Sony Mobile Communications AB –
22(68)

Problem Areas: Vibrator
3. If the BtB connector of Display Frame Assy FPC or FPC is
damaged – replace the Display Frame Assy.
4. Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
23(68)

Problem Areas
1.10 Camera
1.10.1 Main Camera
Check:
Inspect the external area of camera window.
Action:
1. If dirty – clean it.
Troubleshooting Guide (mech)
2. If scratched or damaged – replace the Window Back Sub
Assy.
Check:
Inspect the BtB connector of Camera to Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the BtB connector or the Camera is damaged – replace
the Camera.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
24(68)

Problem Areas: Camera
1.10.2 Video Call Camera defects
Check:
Inspect the external area of the video camera window.
Action:
1. If dirty – clean it.
Troubleshooting Guide (mech)
2. If scratched or damaged – replace the Display Frame
Assy.
Check:
Inspect the ZIF connector of Chat Camera to the Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean the both sides of the ZIF
connector.
3. If the FPC or the Chat Camera is damaged – replace the
Chat Camera.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
25(68)

Problem Areas
1.11 Flash LED
1.11.1 Flash LED not flashing
Check:
Inspect the external area of the flash LED window.
Action:
1. If dirty – clean it.
Troubleshooting Guide (mech)
2. If scratched or damaged – replace the Window Back Sub
Assy.
Check:
Inspect the Flash LED Light Guide on the Sub Antenna
Assy.
Action:
1. If dirty – clean it.
2. if scratched or damaged – replace the Sub Antenna
Assy.
1279-7185 Rev 1
Sony Mobile Communications AB –
26(68)

Problem Areas: Flash LED
Check:
Inspect the flash LED on the Main PBA.
Action:
1. If dirty – clean it.
2. Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
27(68)

Problem Areas
1.12 Bluetooth and WLAN
1.12.1 Bluetooth or WLAN connection
failure
Check:
Inspect the BT + WLAN Flex Antenna contact pads on Sub
Antenna Assy and the contact pins on main PBA.
Action:
1. If dirty or oxidized – clean the pads and pins.
Troubleshooting Guide (mech)
2. If the contact pads on Sub Antenna Assy or BT + WLAN
Flex Antenna film is damaged – replace the Sub Antenna
Assy.
3. If the contact pins on main PBA is damaged – replace
Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
28(68)

Problem Areas
1.13 NFC
1.13.1 NFC malfunctions
Check:
Inspect the NFC antenna contact pads on Sub Antenna
Assy and the contact pins on Main PBA.
Action:
1. If dirty or oxidized – clean the pads and pins.
Troubleshooting Guide (mech)
2. If the NFC antenna contact pads or NFC antenna film is
damaged – replace the Sub Antenna Assy.
3. If the contact pins on main PBA is damaged – replace
Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
29(68)

Problem Areas
1.14 GPS
1.14.1 GPS malfunctions
Check:
Inspect the Diversity/GPS antenna contact pads on Sub
Antenna Assy and the contact pins on Main PBA.
Action:
1. If dirty or oxidized – clean the pads and pins.
Troubleshooting Guide (mech)
2. If the Diversity/GPS antenna contact pads or
Diversity/GPS antenna film is damaged – replace the Sub
Antenna Assy.
3. If the contact pins on main PBA is damaged – replace
Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
30(68)

Problem Areas
1.15 Compass
1.15.1 Compass fails
Check:
Inspect the BtB connector of FPC Assy Relay/Side Key to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the BtB connector of FPC Assy Relay/Side Key or FPC
is damaged – replace the FPC Assy Relay/Side Key.
Check:
Inspect the compass chip on the FPC Assy Relay/Side Key.
Action:
1. If the compass chip is damaged – replace the FPC Assy
Relay/Side Key.
2. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
31(68)

Problem Areas
1.16 Accelerometer
1.16.1 Accelerometer test fails
Action:
Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
32(68)

Problem Areas
1.17 Gyroscope
1.17.1 Gyroscope test fails
Action:
Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
33(68)

Problem Areas
1.18 Ambient Light Sensor
1.18.1 Light Sensor malfunctions
Check:
Inspect the external window area of light sensor on the
Display Frame Assy.
Action:
1. If dirty – clean it.
Troubleshooting Guide (mech)
2. If scratched or damaged – replace the Display Frame
Assy.
Check:
Inspect the BtB connector of FPC Assy Audio Jack to Main
PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the BtB connector or FPC of FPC Assy Audio Jack is
damaged – replace the FPC Assy Audio Jack.
1279-7185 Rev 1
Sony Mobile Communications AB –
34(68)

Problem Areas: Ambient Light Sensor
Check:
Inspect the sensor on the FPC Assy Audio Jack.
Action:
1. If dirty or clogged – clean it.
Troubleshooting Guide (mech)
2. If damaged – replace the FPC Assy Audio Jack.
3. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
35(68)

Problem Areas
1.19 Proximity Switch
1.19.1 Proximity switch malfunctions
Check:
Inspect the external window area of light sensor on the
Display Frame Assy.
Action:
1. If dirty – clean it.
Troubleshooting Guide (mech)
2. If scratched or damaged – replace the Display Frame
Assy.
Check:
Inspect the BtB connector of FPC Assy Audio Jack to Main
PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the BtB connector or FPC of FPC Assy Audio Jack is
damaged – replace the FPC Assy Audio Jack.
1279-7185 Rev 1
Sony Mobile Communications AB –
36(68)

Problem Areas: Proximity Switch
Check:
Inspect the sensors on the FPC Assy Audio Jack.
Action:
1. If dirty or clogged – clean it.
Troubleshooting Guide (mech)
2. If damaged – replace the FPC Assy Audio Jack.
3. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
37(68)

Problem Areas
1.20 Pressure Sensor
1.20.1 Pressure Sensor test fails
N/A. No Pressure sensor in the phone.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
38(68)

Problem Areas
1.21 Water Resistance
1.21.1 Water Resistance fails
Check:
Inspect the Cap SIM.
Action:
1. If dirty – clean it.
2. If not properly assembled – disassemble and reassemble.
Troubleshooting Guide (mech)
3. If the Cap SIM is damaged – replace it.
Run the Water Resistance Test again!
Check:
Inspect the Cap USB.
Action:
1. If dirty – clean it.
2. If not properly assembled – disassemble and reassemble.
3. If the Cap USB is damaged – replace it.
Run the Water Resistance Test again!
1279-7185 Rev 1
Sony Mobile Communications AB –
39(68)

Problem Areas: Water Resistance
Check:
Inspect the FPC Assy Audio Jack.
Action:
If not properly assembled or damaged – replace it.
Run the Water Resistance Test again!
Troubleshooting Guide (mech)
Check:
Inspect the Magnetic charger connector.
Action:
If not properly assembled or damaged – replace it.
Run the Water Resistance Test again!
1279-7185 Rev 1
Sony Mobile Communications AB –
40(68)

Problem Areas: Water Resistance
Check:
Inspect the film for water resistance check.
Action:
If damaged – replace the Display Frame Assy.
Run the Water Resistance Test again!
Troubleshooting Guide (mech)
Check:
Inspect the Ear Speaker.
Action:
If damaged – replace the Ear Speaker and Adhesive
Earspeaker.
Run the Water Resistance Test again!
1279-7185 Rev 1
Sony Mobile Communications AB –
41(68)

Problem Areas: Water Resistance
Check:
Inspect the secondary microphone.
Action:
If damaged – replace the Window Back Sub Assy.
Run the Water Resistance Test again!
Troubleshooting Guide (mech)
Check:
Inspect the Main Antenna Speaker Sub Assy and
loudspeaker sealing rubber.
Action:
1. If dirty – clean it.
2. If Main Antenna Speaker Sub Assy is not properly
assembled – disassemble and reassemble.
3. If the Main Antenna Speaker Sub Assy is damaged –
replace it.
1279-7185 Rev 1
Sony Mobile Communications AB –
42(68)

Problem Areas: Water Resistance
4. If the loudspeaker sealing rubber is damaged – replace
the Display Frame Assy.
Run the Water Resistance Test again!
Check:
Inspect the edge of Display Frame Assy for damage and
gap.
Troubleshooting Guide (mech)
Action:
1. If the edge of Display Frame Assy has gap – replace it.
2. If the Display Frame Assy is damaged – replace it.
Run the Water Resistance Test again!
Check:
Inspect the edge of Window Back Sub Assy for damage and
gap.
1279-7185 Rev 1
Sony Mobile Communications AB –
43(68)

Problem Areas: Water Resistance
Action:
1. If the edge of Window Back Sub Assy has gap –
reassembly it.
2. If damaged – replace it.
Run the Water Resistance Test again!
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
44(68)

Problem Areas
1.22 Real Time Clock
1.22.1 Real time clock test fails
Action:
Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
45(68)

Problem Areas
1.23 Total call time
1.23.1 Total call time fails
Action:
Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
46(68)

Problem Areas
1.24 External
1.24.1 Memory Card not detected
N/A.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
47(68)

Problem Areas
1.25 Security
1.25.1 Security fails
Action:
Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
48(68)

Problem Areas
1.26 FM Radio
1.26.1 No/Poor FM Radio reception
Check:
Inspect the external port of the Audio Jack.
Action:
1. If dirty or oxidized – clean it.
Check:
Inspect the BtB connector of FPC Assy Audio Jack to Main
PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the BtB connector or FPC of FPC Assy Audio Jack is
damaged – replace the FPC Assy Audio Jack.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
49(68)

Problem Areas
1.27 Battery Health test
1.27.1 Battery Health test fails
N/A.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
50(68)

Problem Areas
1.28 Flip Slider Counter
1.28.1 Flip Slider Counter fails
N/A. Not slider phone.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
51(68)

Problem Areas
1.29 Verify Certificates
1.29.1 Verify Certificates fails
Action:
N/A.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
52(68)

Problem Areas
1.30 IrDA Test
1.30.1 IrDA test fails
N/A. No IrDA functionality in the phone.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
53(68)

Problem Areas
1.31 TV-Out Test
1.31.1 TV-Out test fails
Check:
Inspect the USB connector.
Action:
1. If dirty or oxidized – clean the connector.
2. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
Troubleshooting Guide (mech)
54(68)

Problem Areas
1.32 Network & Signal
1.32.1 No/Poor signal
Check:
Inspect the main antenna film on the Main Antenna Speaker
Sub Assy.
Troubleshooting Guide (mech)
Action:
If damaged – replace the Main Antenna Speaker Sub Assy.
Check:
Inspect the contact pads on the Main Antenna Speaker Sub
Assy and the contact pins on PBA Sub.
Action:
1. If dirty or oxidized – clean the pads and pins.
2. If the contact pads are damaged – replace the Main
Antenna Speaker Sub Assy.
1279-7185 Rev 1
Sony Mobile Communications AB –
55(68)

Problem Areas: Network & Signal
3. If the contact pins are damaged – replace the PBA Sub.
Check:
Inspect the RF connector of RF Cable to the PBA Sub.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the connector on the PBA Sub is damaged – replace
PBA Sub.
4. If the RF cable is damaged – replace the RF cable.
1279-7185 Rev 1
Sony Mobile Communications AB –
56(68)

Problem Areas: Network & Signal
Check:
Inspect the RF connector of RF Cable to the Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the RF cable is damaged – replace the RF cable.
4. If the connector on the main PBA is damaged – replace
Main PBA.
Check:
Inspect the Diversity/GPS antenna contact pads on Sub
Antenna Assy and the contact pins on Main PBA.
Action:
1. If dirty or oxidized – clean the pads and pins.
1279-7185 Rev 1
Sony Mobile Communications AB –
57(68)

Problem Areas: Network & Signal
2. If the Diversity/GPS antenna contact pads or
Diversity/GPS antenna film is damaged – replace the Sub
Antenna Assy.
3. If the contact pins on main PBA is damaged – replace
Main PBA.
Troubleshooting Guide (mech)
Check:
Inspect the 2
nd
GSM antenna film on the Main Antenna
Speaker Sub Assy.
Action:
If damaged – replace the Main Antenna Speaker Sub Assy.
1279-7185 Rev 1
Sony Mobile Communications AB –
58(68)

Problem Areas: Network & Signal
Check:
Inspect the contact pad on the Main Antenna Speaker Sub
Assy and contact pin on the FPC Assy Relay/Side Key.
Action:
1. If dirty or oxidized – clean the pin and pad.
Troubleshooting Guide (mech)
2. If the contact pad is damaged – replace the Main Antenna
Speaker Sub Assy.
3. If the contact pin is damaged – replace the FPC Assy
Relay/Side Key.
Check:
Inspect the RF connector of FPC Assy 2nd Antenna to the
FPC Assy Relay/Side Key.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
1279-7185 Rev 1
Sony Mobile Communications AB –
59(68)

Problem Areas: Network & Signal
3. If the connector on the FPC Assy Relay/Side Key is
damaged – replace FPC Assy Relay/Side Key.
Troubleshooting Guide (mech)
4. If the FPC Assy 2nd Antenna is damaged – replace the
FPC Assy 2nd Antenna.
Check:
Inspect the RF connector of FPC Assy 2nd Antenna to the
main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
3. If the FPC Assy 2nd Antenna is damaged – replace it.
1279-7185 Rev 1
Sony Mobile Communications AB –
60(68)

Problem Areas: Network & Signal
4. If the connector on the main PBA is damaged – replace
Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
61(68)

Problem Areas
1.33 SIM
1.33.1 SIM not detected
Check:
Inspect the external port of the SIM card holder and check if
a SIM card can be properly inserted.
Action:
If dirty or clogged – clean the external port.
Troubleshooting Guide (mech)
Check:
Inspect the SIM Tray.
Action:
1. If the SIM Tray is damaged – Replace it.
Check:
Inspect the SIM card holder on Main PBA.
Action:
1. If dirty or clogged – clean the holder.
2. Replace Main PBA.
1.33.2 Incorrect UIM or SIM indicated
Check:
Check whether the phone is locked to a particular operator
and whether the correct operator UIM or SIM is being used.
Action:
1. Use a proper operator UIM/SIM or test UIM/SIM.
2. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
62(68)

Problem Areas
1.34 Charging
1.34.1 Battery will not charge by USB
connector
Check:
Inspect the USB connector.
Action:
1. If dirty or oxidized – clean the connector.
2. Replace Main PBA.
Check:
Inspect the BtB Connector of the Battery to Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean the both sides of the BtB
connector.
Troubleshooting Guide (mech)
3. If the BtB connector, the Battery FPC or Battery is
damaged – replace the Battery.
4. Replace Main PBA.
1.34.2 Battery will not charge by
charge pad
Check:
Inspect the external port of the Magnetic Charger
Connector.
Action:
If dirty or oxidized – clean it.
1279-7185 Rev 1
Sony Mobile Communications AB –
63(68)

Problem Areas: Charging
Check:
Inspect the BtB connector of the FPC Assy Charger Pad to
Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean the both sides of the BtB
connector.
3. If the BtB connector or FPC of the FPC Assy Charger Pad
is damaged – replace the FPC Assy Charger Pad.
Troubleshooting Guide (mech)
Check:
Inspect the contact pins on FPC Assy Charger Pad and
pads on Magnetic Charger Connector.
Action:
1. If dirty or oxidized – clean the pins and pads.
2. If the contact pads of Magnetic charger connector are
damaged – replace the Magnetic charger connector.
1279-7185 Rev 1
Sony Mobile Communications AB –
64(68)

Problem Areas: Charging
3. If the contact pins of the FPC Assy Charger Pad are
damaged – replace the FPC Assy Charger Pad.
Check:
Inspect the BtB Connector of the Battery to Main PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean the both sides of the BtB
connector.
Troubleshooting Guide (mech)
3. If the BtB connector, the Battery FPC or the Battery is
damaged – replace the Battery.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
65(68)

Problem Areas
1.35 HandsFree by Wire
1.35.1 Connection to portable
Handsfree fails
Check:
Inspect the external port of the Audio Jack.
Action:
1. If dirty or oxidized – clean it.
Check:
Inspect the BtB connector of FPC Assy Audio Jack to Main
PBA.
Action:
1. If not properly connected – disconnect and reconnect it.
2. If dirty or oxidized – clean it.
Troubleshooting Guide (mech)
3. If the BtB connector of FPC Assy Audio Jack or FPC is
damaged – replace the FPC Assy Audio Jack.
4. Replace Main PBA.
1279-7185 Rev 1
Sony Mobile Communications AB –
66(68)

Problem Areas
1.36 Data Communication
1.36.1 Data transfer via System
Connector fails
Check:
Inspect the USB connector.
Action:
1. If dirty or oxidized – clean the connector.
2. Replace Main PBA.
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
67(68)

2 Revision History
1 2013-Dec-06 Initial release
Troubleshooting Guide (mech)
1279-7185 Rev 1
Sony Mobile Communications AB –
68(68)