FLY E146 Service Manual

E146_Maintenance Instruction

Prepared by：xiaoyu wan
Approved by：
Date：2010.9.28

TABLE OF CONTENTS

1 Overview E146

1.1 About E146 Phone

1.2 Distribution of the mainboard components

2 RF

2.1 RF Overview

2.2 Transmit

2.3 Receive

2.4 Common RF Malfunction

3 Baseband

3.1 Baseband Overview

3.2 Logic

3.3 Power management

3.4 Baseband common malfunction

4 Reference for maintenance

4.1 No power on

4.2 Shut off automatically

4.3 Dead halt

4.4 No charge

4.5 Quantity of electricity faulty detection

4.6 No display

4.7 LED NG (on the LCD)

4.8 LED NG (on the keyboard)

4.9 Key NG

4.10 No ring

4.11 No receiving voice

4.12 No sending voice or voice is small

4.13 No vibration

4.14 SIM card inefficacy

4.15 TF card inefficacy

4.16 Camera inefficacy

4.17 Bluetooth inefficacy

4.18 Earphone inefficacy

4.19 FM inefficacy

4.20 G sensor inefficacy

1 Overview E146

1.1 About E146 Phone

E146 mainboard is based on the MTK platform designed to support 2-band

which supporting the FM and Bluetooth calls and transmission, the
mainboard system consists of the base-band （CPU：
MT6253+PF38F4050M0Y3DEA） and the RF (MT6253+RF7161).

1.2 Distribution of the mainboard components

FM

TY6701111184KC

Camera FPC

RDA5802ES

MT6253

LCD CON

MT6253

RF7161

RF PA

Flash

CPU

Socket of T card

Socket of SIM card Battery CONN

K/B FPC

Antenna

MXC62025MP

G-senser

Adapter CONN

MT6612

BT area

2 RF

2.1 RF Overview
RF part mainly consists of transceiver MT6253 (adopts program of near-zero IF

receiver, supporting the EGSM / DCS and 26M VCTCXO as the clock input,
integrated clock buffer, LO VCO and TX VCO and regulator, only need for
external connections of VBAT / AVDD), RF7161 (it supports EGSM / DCS
and integrated automatic power control and transceiver switch).

Transceiver (MT6253) with the RF modulation and demodulation functions

contains IF frequency synthesizer and VCO RF, which is part of the core
component of the RF. PA has a major role in amplification of modulation
signal, and it must be controllable and the speed should meet the GSM
agreement.

2.2 Transmit
TX is composed of the modulation loop, power amplifier and antenna

switch. PLL is mainly in the internal MT6253, I / Q signal first
enters into the MT6253, after entering the PLL the signal is
modulated to RF, and then it outputs from the chip to PA, converts
into electromagnetic energy through antenna by the antenna

switch after enlarged.
PA:
This part adopts voltage control to achieve and its role is to amplify

the signal power in accordance with the requirements. It is divided

to two different power levels through VRAMP signal. The transmit

signal of GSM is 5 to 19, power is from 3.2MW to 2W while DCS is

0 ~ 15, power from 1MW ~ 1W. PA is time-sharing work controlled

by TX-EN chip, the output power of PA is controlled by VRAMP

(APC) through the voltage. PA is intermittent work, by the BS to

achieve the choice of frequency bands.

2.3 Receive
Antenna RX - MT6253 (RX_VCO mixer) - band-pass - Amplification -

filter - Amplification - RX_VCO mixer - CPU

2.4 Common RF Malfunction
Detection and Maintenance Flow Chart of MS Transmit malfunctio

3 Baseband

3.1 Baseband Overview

E146 Baseband consists of CPU MT6253 and Program Memory. MT6253
baseband, the core device of the mainboard, is responsible for the normal work
among various parts of mainboard, such as voice processing, image processing,
power management as well as MS communications.

MT6253 digital baseband contains ARM7EJ-S 32-bit core and 144Kbyte SRAM.
MT6253 which is an enhanced GSM Processor integrated Channel Codec
subsystems interiorly including Channel Codec, Intertlace / Deinterleave,
Encryption / Decryption and Control Processor subsystems including ARM7EJ-S
and its peripheral circuits. There are 25 address lines,16 data lines, 8 chip select
lines, provided 7 external interrupt Interface, 52M/104M operation clock.

Analog baseband contains MT6253 analog baseband chip, audio, baseband
codec and power management. Four major functional blocks integrated internal:
Audio codec including Voice input / Output channel, Buzzer output; Baseband
codec including Differential I, Q input / output, GMSK modulation and A / D, D / A;
Auxiliary parts including AFC DAC, RAMP DAC, AGC DAC and a seven-channel
A / D. And WATCHDOG interface is set internal to enhance the stability of the
system.

3.2 Logic

Logic part is composed of MTK base-band management chip MT6253, power
management chip MT6253 and Nor Flash.

 CPU ： MT6253
 Nor Flash：PF38F4050M0Y3DEA
 PMU ： MT6253

3.3 Power management

Power management consists of the charging circuit integrated in MT6253 and the
external charging circuit. It provides 11 road LDO voltage. Besides, it completes
the logic level conversion of SIM card. The chip also outputs the system reset
signal.

Boot process:
The normal boot is to press boot key which is that the PWRKEY is being dragged down.
Once the boot key is pressed, all LDO are open except VSIM. After VCORE opening RESET
timer and timer out, RESET is being pitched up to start the digital baseband chip, that is,
UMT6253 starts to run and roll polling its ROWX pin, pitch up its PWRONIN pin, then you can
release the boot key. This is the initial boot process.

3.4 Baseband common malfunction

3.4.1 Nor Flash programming does not download

Data lines used for downloading software: VBAT, TX, RX, GND, CHARGE. It is
mostly due to the false solder and wire bonding. First check whether the serial port
of PC and cell phone is unrestricted, if not, it is caused by being lack of devices or
empty solder of power manager, USB-con and peripheral resistance. Measure the
TX, RX signals by using AC-coupled oscilloscope to track the signal flow, if a
certain period circuit of no signal it may be AC short circuit to ground, or is caused
by a short circuit and open circuit. On checking the malfunctions, first should
carefully observed the welding of these devices with a magnifying glass, then plug
in the download line to observe whether the current is normal, there is short-circuit
to ground of VCHG or VBAT if the current is large, at this time cut off power supply
as soon as possible, and then find the short-circuit point. It may be the abnormal
output power supply of a certain circuit that the current is larger than normal
(about 30 mA) but not particularly large, at this time should check whethe the
valgate of VCORE (1.8V), VDD (2.8V), VADD (2.8 V), VTCXO (2.8V), VRTC
(1.5V), VMEM (2.8V) is noamal, if not, bad welding can be detected. Focus on
checking the welding of PMU and USB-CON if there is a little or no current.
Unplug and re-plug the download line to see if it is caused by poor contact; It can
test that whether the output of 26MHz clock signal to the CPU is normal by using
oscilloscope.

3.4.2 Detection and Maintenance Flow Chart of No download malfunction

4 Reference for maintenance

4.1 No power on

No power on

Check whether the

battery voltage is

higher than 3.4V

Y

Check whether the battery

and the key pad is

oxidized or there is

anything else on it

N

Check whether the

connection of KEY PCB &

MB is OK

Y

Take out the LCD and

SPK, Check whether it is

powered on

N

Y

N

Y

Charge the battery

Wipe off the thing

or clean the key pad

Reassemble or Charge

the KEYPAD FPC

Cross-testing the

LCD&SPK,

Change the defective

N

C1119:1.8V
C1119:2.8V,
C1120:2.8V,
C1121:2.8V,
C1122:2.8V,
C1123:2.8V,

Check whether

R4401，R1107 is

broken

N

Connect with the battery,

press “ON” key, check

whether the output voltage

of U1100 is normal

Y

Y

Change R4401,R1107

Replace the earthed capacitor

NN

corresponding to the

defective pin, Check whether

ChangeU1100

it is OK

Check whether the output

frequency of X1100 is 32.768K

Y

N

ChangeX1100，

C1100，C1101

Check whether the output voltage

of U2602 pin 3 is 0.5V around

Y

N

Change U2602

N

Change U2605

Change the Flash (U1101),

check whether it is OK

Y

ChangeU1100

OK

N

Change U1101

4.2 Shut off automatically

Shut off automatically

D/L the latest software,
Check whether it is OK

N

Replace with a

good battery, Check

whether the

primary cell is broken

N

Check whether the

rubber, used to fix the

battery, is lost or at the

other location

N

Check whether the battery

and the Connector of J9410 is

oxidized or there is

anything else on them

Y

Y

Y

Y

ok

Change the battery

Reassemble the

rubber

Wipe off the thing

or clean the Connector

N

N

Check whether the contact of

the key PAD & the dome is OK

Y

Check whether X1100

output frequency is

32.768K exactly
Y

Refer to the maintenance

method of ‘No power on’

OK

N

N

Reassemble the dome

ChangeX1100,

C1113,C1114

4.3 Dead halt

Dead halt

D/L the latest software,
Check whether it is OK

N

Replace with a good

battery, Check whether

the primary cell is broken

N

Check whether the
problem is resulted

from ‘KEY NG’

N

Check whether the
problem is resulted
from the LCD itself

Y

Y

Y

Y

ok

Change the battery

Clean the K/B,

reassemble or change

the metal dome

Change the LCD

N

Check whether the

output frequency of

X1100 is 32.768 exactly

Y

N

ChangeX1100,

C1113,C1114

Check whether the contact of

the key PAD & the dome is OK

Y

Replacing with the

programming FLASH,

check whether it is OK

N

Refer to the servicing

method of ‘No power on’

N

Reassemble

the dome

OK

4.4 No charge

No charge

Replace with a good

adaptor, Check

whether the primary

adaptor is broken

N

Replace with a

good battery, Check

whether the

primary cell is broken

N

Check whether the

battery connector ‘J9410’

is oxidized or is broken

N

Check whether the
Micro USB ‘J9431’

is oxidized or is broken

Y

Y

Y

Y

Change the adaptor

Change the battery

Clean or

change J9410

Clean or

change J9431

N

Plug in, Check whether it has an

voltage of 5V on B1103

Y

N

Change B1103

BLM18EG221TN1

Check whether there is broken of

U1102, R1105,C1131, Z1340

N

ChangeU1100

OK

Y

Change the defective

4.5 Quantity of electricity faulty detection

Quantity of electricity

faulty detection

Replace with a good battery,

Check whether the primary cell

is broken

N

Format and Download the latest

Software, then calibrate the

ADC

N

Check whether there is broken

of D1300

N

ChangeU1100

Y

Change the battery

Y

Change the defective

OK

4.6 No display

No display

Download the latest Software,

Check whether it is OK

N

Check whether the LCD is

weakly welded or broken

N

ChangeU1100

OK

Y

Y

ok

Re-weld or change

the LCD

4.7 LED NG (on the LCD)

LED NG (LCD)

Check whether the

LCD is broken

N

Check whether

C4400 C4402 C4441~C4444

is broken

N

Check whether

L1106 L1102 C1132 C1133

is broken

N

ChangeU1100

Y

Change the LCD

Y

Change U4400

Y

Change U4400

OK

4.8 LED NG (on the key board)

LED NG (key)

Checking method:

Crosstesting

the two sides of

LED by Multimeter ,

gearing to the short circuit,

if the LED is on at one

direction, it shows good

Check whether there

is anything (or Mylar)

on the key

N

Check whether the

LED of the KEYPD is

weakly welded or

broken

N

Check whether the
resistor beside the

LED is broken

N

Y

Y

Y

Clean or wipe off

the thing

Re-weld or

change the LED

Change the resistor

Check whether the

connection of sliding PCB &

MB is OK

Y

N

Reassemble or Charge

the sliding FPC

Check whether

R4409 C4490 C4491

is broken

N

Check U1100

OK

Y

Change R4409 C4490

C4491

4.9 Key NG

Key NG

Check whether there is

anything oxidized or

smudge on the key pad

N

Check whether the

metal dome is oxidized

or broken
N

Check whether the

connection of KEY PCB &

MB is OK

Y

Y

Y

N

cleaning the key pad

Change the
metal dome

Reassemble or Charge

the KEY FPC

Check whether the

D4417~D4420 D4429~D4434

is broken

N

Change CPU(U1100)

OK

Y

Change the defective

4.10 No ring

No ring

Checking methodtesting

the resistance of the SPK

by Multimeter, gearing to

the resistance, the

resistance of it is 8ohm

normally

D/L the latest edition,

Check whether it is OK

N

Check whether the connection

of J9401 is OK

Y

Check whether the

SPK is void-welded

or broken

N

Check whether L3300 L3301

B3307 B3308 C3306 C3307

C3322 C3323 D3304 D3305

N

Y

N

Y

ok

Reassemble the

Connector

Re-weld or

change the SPK

Y

Change the defective

Change the CPU

OK

4.11 No receiving voice

No receiving voice

Checking methodtesting

the resistance of the REC

by multimeter, gearing to

the resistance, the

resistance of it is 30ohm

around

D/L the latest edition,

Check whether it is OK

N

Check whether the connection

of J9401 is OK

Y

Check whether the

REC PAD is oxidized

or broken

N

Check whether the

C3313~3315 B3320 B3321

D3320 D3321 is broken

N

Y

Y

N

Y

Ok

Reassemble the

Connector

Clean or

Change the REC

Change the defective

Change the CPU

OK

4.12 No sending voice or the voice is small

No sending voice

or a small voice

Checking method

testing the resistance of

the MIC by multimeter,

gearing to the resistance,

the positive resistance of

it is 1K, the opposite is

0.8K around in general

D/L the latest edition,

Check whether it is

OK

N

Check whether the MIC

rubber is broken or

displacement

N

Check whether the

MIC is weakly welded

or broken

N

Check whether there is

anyone broken of

R3305~3308

Y

Y

Y

Y

ok

Reassemble or change

the MIC rubber

Re-weld or

change the MIC

Change the defective

N

check whether there is

anyone broken of C3308~3312,

B3300, B3301,D3301, D3302

N

Change the CPU

OK

Y

Change the defective

4.13 No vibration

No vibration

Checking methodtesting
the resistance of the motor

by multimeter, gearing to

the resistance, the

resistance of it is 22ohm in

general

D/L the latest edition,

Check whether it is OK

N

Check whether the connection

of J9401 is OK

Y

Check whether the

motor is locked by

displacement

N

Check whether the

motor is broken

N

Y

Y

Y

N

ok

Reassemble the

Connector

Reassemble

the motor

Change the motor

Check whether there is

anyone broken of R1302

C1301 B1300 B1301

N

Change the CPU

Y

Change R1302

C1301 B1300 B1301

OK

4.14 SIM Card inefficacy

SIM Card inefficacy

D/L the latest edition, check

whether it is OK

N

Check whether the SIM

card is broken

N

Check whether the SIM

Card Connector J9420

is broken

N

Check whether there is

anyone broken of C4423 C4424

D4421-D4426

Y

Y

Y

Y

ok

Change the SIM card

Change the defective

Change the defective

N

Change the CPU

OK

4.15 TF card inefficacy

TF NG

D/L the latest edition,

check whether it is OK

N

Check whether the

socket ‘J9406’ is

void-welded or broken

N

Check whether there is

anyone broken of C4433

C4434

N

Change the CPU

Y

Y

OK

Re-weld or Change J9406

Y

Change the defective

OK

4.16 Camera inefficacy

Camera NG

Change B4410

Check whether the connection

of J9401 & Camera is OK

Y

Check whether the

camera is broken

N

Check whether J9401
pin6 has an voltage of

2.8V,pin4 has 1.8V

Y

Y

Check whether

B4410 is broken

N

Y

N

C4420 are voidwelded or broken

N

Reassemble the

Connector

Change the Camera

Check whether C4410~4415,

N

Change the CPU

Y

Change

the defective

OK

4.17 Bluetooth circuit(MT6612)

Bluetooth is a design feature of this cellphone. It is with a matching Bluetooth headset and the
phone has a container which can charge up Bluetooth headset through the main board, to
accommodate Bluetooth headset. Some of the projects may not have this function, however, the
mainboard is compatible. Please first ensure that the power is correct, according to the
phenomenon and following schematic diagram to maintain the phone.

4.17 Bluetooth inefficacy

BT NG

D/L the latest edition,

check whether it is OK

N

Check whether the

BT antenna is

touched well

Y

Check whether

C5307 is void-welded

or broken
N

Check whether U5301,

C5300 are voidwelded or broken

Y

N

Y

Y

ok

Reassemble the

antenna

Change C5307

Change

the defective

N

Y

Change U5300

Enable the BT function,

check whether C5302
has a voltage of 2.8V,

C5305 has 1.2V

Y

Check whether

C5301 has an output

frequency of 26M

Y

Change U5300, check

whether it is OK

N

N

N

Check whether

the voltage at R5301

is the high level

Change C5301, C2637

N

Change CPU

Change the CPU

OK

4.18 Earphone inefficacy

Earphone inefficacy

Check whether the

earphone is broken

N

D/L the latest edition,

check whether it is OK

N

Check whether

the IO

connector ‘J9431’

is broken

N

After inserting the

earphone, Check

whether the voltage at

R3300 is 0V around

Y

Y

Y

Change the earphone

ok

Change J9431

N

Change R3300(1K),

C3319, B3305

Y

No sending voice of

the earphone MIC

No receiving voice of the

earphone receiver

Check whether there is anyone

Y

Change the defective Change the defective

broken of C3300~C3304, R3301-

R3303, B3306, C3351, C3320

NN

Change the CPU U1100

Check whether there is anyone

broken of R3300, R3309 R3310,

C3316~3319, B3304, B3305

Y

OK

4.19 FM inefficacy

FM NG

D/L the latest edition,

Check whether it is OK

N

Y

ok

Enable FM function,

check whether C5311

has a voltage of VBAT,

C5312 has a voltage of 2.8V

Y

check whether there is

anyone broken of C5309,

C5401, B5401

N

N

Change C5311, C5312, C5315

Y

Change the defective

Check whether the

output frequency of

C5310 is 32.768K

Y

N

Change C5310

check whether there is

anyone broken of C5313,

C5314

N

Change U5303

N

Change the

CPU

OK

Y

Change the defective

4.20 G sensor inefficacy

G sensor inefficacy

D/L the latest edition,

Check whether it is OK

N

Check whether

U4302 is broken

N

Change the CPU

Y

ok

Y

Change U4302

OK