Nokia Customer Care
6235/6235i/6236i (RM-60)
Mobile Terminals
Baseband Description and
Troubleshooting
Issue 1 04/2005 Company Confidential ©2005 Nokia Corporation
6235/6235i/6236i (RM-60)
Baseband Description and Troubleshooting
Contents Page
Introduction ..................................................................................................................................................... 5
Power Up Sequence ....................................................................................................................................... 7
Flash Programming ........................................................................................................................................ 8
Flashing Tool .................................................................................................................................................8
Flashing Phoenix Interface .......................................................................................................................9
Audio.................................................................................................................................................................. 9
How the Audio Works ................................................................................................................................9
Audio Troubleshooting .............................................................................................................................10
Audio Phoenix Interface ..........................................................................................................................12
Camera............................................................................................................................................................ 12
How the Camera Works ...........................................................................................................................12
Camera Troubleshooting ..........................................................................................................................13
Camera Phoenix Interface .......................................................................................................................14
FM Radio ........................................................................................................................................................ 15
How the FM Radio Works .......................................................................................................................15
FM Radio Test .............................................................................................................................................15
FM Radio Troubleshooting ......................................................................................................................15
FM Radio Phoenix Interface ...................................................................................................................16
USB (Universal Serial Bus)......................................................................................................................... 17
How USB Interface Works .......................................................................................................................17
USB Troubleshooting ................................................................................................................................18
USB Phoenix Interface .............................................................................................................................20
Display ............................................................................................................................................................ 21
How the Display Works ............................................................................................................................21
Display Troubleshooting ..........................................................................................................................21
Display Backlight Troubleshooting .......................................................................................................22
Display Phoenix Interface .......................................................................................................................24
Keypad Backlight ......................................................................................................................................... 24
How the Keypad Backlight Works ........................................................................................................24
Keypad Backlight Troubleshooting .......................................................................................................25
Keypad Backlight Display Phoenix Interface .....................................................................................27
GPS................................................................................................................................................................... 27
How GPS Works .........................................................................................................................................27
GPS Troubleshooting ................................................................................................................................28
GPS Phoenix Interface ..............................................................................................................................31
SIM Card......................................................................................................................................................... 31
How SIM Card Works ...............................................................................................................................31
SIM Card Troubleshooting ......................................................................................................................32
Sim Card Phoenix Interface ....................................................................................................................35
Infrared........................................................................................................................................................... 35
How Infrared Works ..................................................................................................................................35
Infrared Troubleshooting .........................................................................................................................36
Infrared Phoenix Interface ....................................................................................................
System Connector........................................................................................................................................ 38
Accessory Detection.................................................................................................................................... 39
Battery (Lynx) Interface Circuit............................................................................................................... 40
PWB Overview .............................................................................................................................................. 41
..................37
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Bottom Board .............................................................................................................................................41
Top Board .....................................................................................................................................................42
Main Test Points .......................................................................................................................................... 43
Current Test Points ....................................................................................................................................43
Current too High at Zero Test ................................................................................................................43
Terminal in Local Mode Test ...................................................................................................................44
Display Test .................................................................................................................................................45
Charging Test ..............................................................................................................................................45
Common Problems ...................................................................................................................................... 46
No Communication During Flash ..........................................................................................................46
No Communication During Alignment ................................................................................................46
Failed Self Test/Calibrate .........................................................................................................................47
Phone Not Powering Up ..........................................................................................................................47
Shut Down After 32 Seconds .................................................................................................................47
No Audio ......................................................................................................................................................47
Key Pads Malfunction ..............................................................................................................................47
No LCD Display ...........................................................................................................................................48
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Baseband Description and Troubleshooting Nokia Customer Care
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Nokia Customer Care Baseband Description and Troubleshooting
Introduction
The 6235/6235i/6236i baseband module is a tri-mode, Code Division Multiple Access
(CDMA), dual-band engine and is based on the DCT4.5 standard. The baseband engine
includes two major Application Specific Integrated Circuits (ASICs):
• D2200 or UEMEK 2VO — Universal Energy Management Enhanced Integrated
Circuit (UEME IC), which includes the audio circuits, charge control, and voltage
regulators
• D2800 or TIKUEDGE v1.1 — Main mobile terminal processor, which includes
system logic for CDMA, two Digital Signal Processors (DSPs), the Main Control
Unit (MCU), and the memory
The BL-6C Li-ion battery is used as the main power source and has a nominal capacity of
1070 mA/h.
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Baseband Description and Troubleshooting
Battery
UHS Jack
DC Jack
Tomahawk
Antenna
Bluetooth
Zocus
Nut
USB
Production
Test IF
Sim MMC
D2200
32 KHz
Amplifier
Regulator
Mic
IHF Speaker
Regulation
Charge Control
EarPiece
Audio
FBUS / MBUS
Vibra
SIM I/F
Disp BL’s
RTC
VIO
CBUS
RF
D
B
U
S
PWM
PWM
Cam Flash
Int Display
Parallel
Ext Display
GPS
PCM / UART
UART
D2800
MCU ARM925
19.2 MHz
FM Radio
Flash Memory
(Program,
NOR)
Flash Memory
(User, NAND)
PDRAM
C-DSP Lead3
A-DSP Lead 3
Serial
Keyboard
EL
2G System Logic
Camera
SDRAM
VCORE
SMPS
IRDA
Figure 1: Baseband block diagram
Even though the Bluetooth, External Display and MMC components are on the ASICs,
they are not used in the 6235/6235i/6236i baseband module.
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Nokia Customer Care Baseband Description and Troubleshooting
Power Up Sequence
When phone is dead or jammed always check the Power Up Sequence of the baseband
area. Verify all regulator and reset signals are correct to ensure proper power up of
UEMEK and D2800 (see Figure 2).
Reference signal
PwrOnX
Charger Detection
RTC
UEMRSTX
VCORE
VFlash1
VIO
VANA
VR3
19.2MHz Clk
PURX
Reset mode is entered and
the watchdog starts
End of settling time (only if Vbat > Vcoff+_);
VFLASH1 regulator enabled
VR3, VANA, VIO, and VCORE enabled;
PURX held LOW
D2800 processor, MCU, and DSP are
reset; VCTCXO regulator forced on
Sleep Clock
t1 t2 t4t3
t1 = 20ms
t2 = 200ms
t3 = 500us
t4 = 20ms
Figure 2: Power-on sequence and timing
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Baseband Description and Troubleshooting
Flash Programming
Flashing Tool
Figure 4 shows the DA-54 flashing tool.
Figure 3: Power Up Sequence
Figure 4: DA-54 Flashing Tool
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Nokia Customer Care Baseband Description and Troubleshooting
Flashing Phoenix Interface
Run EZ Flash in Phoenix to flash the phone.
Audio
How the Audio Works
The baseband supports three microphone inputs and two earpiece outputs. The
microphone inputs are MIC1, MIC2, and MIC3:
• MIC1 input is used for the phone's internal microphone,
• MIC2 input is used for headsets (HDB-4),
• MIC3 input is used for the Universal Headset.
Every microphone input can have either a differential or single ended ac connection to
UEMEK circuit. In the Nokia 6235/6235i/6236i, the internal microphone MIC1 and
external microphone MIC2 for Pop-Part™ accessory detection are both differential.
However, the Universal Headset interface is single ended. The microphone signals from
different sources are connected to separate inputs at UEMEK. Inputs for the microphone
Figure 5: EZ Flash in Phoenix
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signals are differential type. Also, MICB1 is used for MIC1 and MICB2 is used for MIC2
and MIC3 (Universal Headset).
UHJ MIC3
MIC2 MIC1
IHF
Audio Troubleshooting
When troubleshooting the audio, make these common checks (see Figure 7):
• Performed visual inspection of all the ASIP’s and UEMEK
• Inject 1KHz signal into MiC1 and trace it all the way to the ear piece. Only when
using IHF signal will be amplify by a factor of 8.
Ear Piece
Figure 6: Audio components
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Audio Amplifier
IHF
FM Radio Lines
Audio ASIP’s
DC Block Caps
Audio ASIP’s
Ear Piece
MIC2
UHJ
MIC3
MIC1
Figure 7: UEMEK Side of Audio Diagram
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Baseband Description and Troubleshooting
Audio Phoenix Interface
Run Audio Test in Phoenix to check the audio functionality.
MiC1- Use first option to route the audio from the
internal microphone to the headset speaker.
MiC2- Use second option to route the audio signal
from the headset microphone to internal ear piece.
MiC3 - To test MIC3 you need to use the first and
second options. Open channel and insert the
universal headset. The UEM automatically re-routes
the audio signal to the UHJ.
Ear Piece - Use second option to hear something
from internal ear piece.
IHF - Use the fifth option to route audio signal to IHF
speaker out.
Camera
How the Camera Works
When you select the view finder to take a picture, the D2800 activates the camera by
turning on GENIO(27) and GENIO(24)9.6MHz. Once the camera is initialized, D2800
sends control commands through the I2C (GENIO (25&26) interface. The camera takes a
Figure 8: Audio Test in Phoenix
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picture and sends data back to D2800 for processing through CCP lines. After D2800
finishes with all image processing, the image is stored in the flash memory.
Figure 9: Camera and HWA connections to the baseband
Camera Troubleshooting
When troubleshooting the camera, make these common checks (see Figure 13):
• Check Power Supply V2.8 and VDIG
• Check Sleepx is high
• Camera Enable GenIO(27) is high
• Check Camera Clk on GenIO(24)
• Check Control line I2C on GenIO 25& 26
• Check raw data lines going back to D2800
• Inspect camera socket and replace Camera
• Check D2800 for Solder problems and replace, if necessary
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Baseband Description and Troubleshooting
V 2.8V
GENIO(27) (EN)
Camera socket inspection
Figure 10: Camera socket and checkpoints
Camera Phoenix Interface
Run Camera Contol in Phoenix to check the camera functionality.
GENIO(24) (9.6Mhz)
GENIO(25)
GENIO(26)
Camera with integrated VGA camera and
camcorder functionality
VDIG 1.8V
Raw Image Data
Use Viewfinder On option to view image
in the PC Window
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Figure 11: Camera Control in Phoenix
FM Radio
How the FM Radio Works
D2800 turns on the FM radio and sets the frequency using CBUS serial interface as the
communication channel. A high frequency FM radio signal come in through RFIN1 Pin to
the FM radio chip, then it gets demodulated into a low frequency signal and send to
UEMEK for amplification. The amplify signal then get routed back to either universal
headset or to the system connector for stereo headset.
Figure 12: FM Radio (N356), Audio (N150), antenna, and digital interface connections
FM Radio Test
To hear the FM radio, you first connect headset to Pop-Part™ or UHJ ports because the
headset will be an FM radio antenna. And you have to connect headset to UHJ port to
control the FM radio by using Phoenix. But if you connect a headset (such as HDS-3) to
Pop-Part™ connector, then you can’t control the phone because you’ve already occupied
the connection port (Pop-Part™), so in this case you have to have jumper wires on
production test points (Fbus Tx/RX,GND).
FM Radio Troubleshooting
When troubleshooting the FM radio, make these common checks (see Figure 13):
• Check Power Supply VIO and VANA
• Check SleepCLK
• Check FMANT
• Check for activity on CBUS
• Check output of FM radio on VAFR and VAFL
• If 6 is not correct, then Check FM radio chip for shorts, voids, and misalignments
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• If 6 is correct, then Check EUMEK for shorts, voids, and misalignments
• If UEMEK and FM Radio Chip is correct, then check system connector
FM Radio Chip (always
the check solder)
VANA (2.8V)
VIO (1.8V)
VAFLVAFR
FMANT
Figure 13: FM Radio Chip and Antenna
FM Radio Phoenix Interface
Checks for the FM radio that you can do with Phoenix include:
• Verify FM radio is working by connecting Headset to UHJ
• Turn on FM radio
• Set frequency and volume
• If FM radio is working then, retest on FinalUI
XEAR_LP
XEARN
FMANT
GND
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Power On check box
Frequency control
Volume control
Figure 14: Phoenix FM Radio Control panel
USB (Universal Serial Bus)
How USB Interface Works
When Phone connects to a computer using a DKU-2 data cable the computer will
provide Vbus (5V) to and pull down D+ a,d D – lines. The phone will respond by pulling
the D+ line high. The computer acknowledges and start transferring data at 12Mbits/sec.
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Baseband Description and Troubleshooting
USB Troubleshooting
First connect phone to computer using a DKU-2 data cable. Check under device manager
to see if the computer recognizes the phone as a USB device. If the phone is recognizes,
there is no hardware fault and you can stop troubleshooting.
When troubleshooting UPS, make these common checks (see Figure 29 and Figure 30):
• Perform visual inspection on Pop-Part™ connector, ESD Protection, NUT Chip, and
caps and Inductors
Figure 15: USB interface block diagram
Figure 16: PC Device Manager
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• Check Vout, Vflash1, and ACI Line. If not correct, check UEMEK under X-ray or
change part.
• Check for activity on the USB D+ and USB D – lines, if nothing check D2800
under X-ray or change part.
USD ESD Protection
VFlash1 (2.8V)
_OE (1.8V)
USB D+ (3.3V)
USB D- (3.3V)
Vout
USB Vbus (5V)
ACI
USB D+
USB D-
Figure 17: USB Chip and Diagram
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USB Phoenix Interface
Run the USB Tests in Phoenix to check the USB functionality:
Figure 18: USB Vout
Figure 19: USB Phoenix Interface
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Display
How the Display Works
Nokia 6235/6235i/6236i has a large 128 x 128 display with 65,536, that D2800 controls
through a serial interface and UEMEK powers using VIO and VFlash1.
Display Troubleshooting
When troubleshooting the display, make these common checks (see Figure 21):
• Check display is connected properly and is making good contact. If not correct,
try replacing the LCD.
• Check the Power Supply VIO and VFlash1. If not correct, check UEMEK.
• Check activity on the LCD test points. If no activity, check or replace D2800.
Figure 20: Nokia 6235/6235i/6236i Display
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Baseband Description and Troubleshooting
VIO
SDA
SCX
SCLK
VFlash1
Figure 21: Display Chips and Frequency
Display Backlight Troubleshooting
When troubleshooting the display backlight, make these common checks (see Figure 29
and Figure 30):
• Perform visual inspection of LCD connector and LED Driver circuitry
• If display backlight is not turning on, check VLED +(~10V) and VLED – (~.5V) on
display connector.
• If there, then you can assume the driver is working properly and the LED inside
the display might be bad. Try changing display.
• Check VLED + and VLED – on Display Driver circuitry.
• Check Dlight is enable high (~4V). If not correct, check UEMEK.
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• Check Rset (33 Ohms)
• Check Vbat(~4V) and Vin(~4V) are present. If not, check power supply
connection.
VLED-
VLED+
VIN
VBat
Display LED Driver
VLED-
Rset
Dlight
VLED+
Figure 22: Display Backlight Chip and Diagram
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Display Phoenix Interface
Run the Display Test and Display Tune in Phoenix to check the display.
Keypad Backlight
Figure 23: Phoenix Display Test option
Figure 24: Phoenix Display Tune option
How the Keypad Backlight Works
Klight coming out of UEMEK controls the keypad backlight LED’s. Dlight enables the LED
driver, which is a constant current supply for all the keypad LED in parallel. The current is
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set for all the branches by Rset which in this case is 12k Ohms and equates to 10mA
through each LED.
Figure 25: Keypad Backlight Diagram
Keypad Backlight Troubleshooting
When troubleshooting keypad backlight, make these common checks (see Figure 29 and
Figure 30):
• Performed visual inspection of all the components including LED’s
• Check Vbat to make sure Driver has power
• Check Klight to make sure driver is enable by UEMEK. If not correct, check
UEMEK
• If light are too dim or too bright, check Rset. Rset controls the current going
through the LED’s.
• Check Vout to make sure LED’s are getting power, if still not working change LED.
Make sure LED orientation is correct.
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Vout (~3.5V)
Iset (0.5V)
Vbat
Klight (~Vbat)
Rset (12k Ohms)
Vout
Figure 26: Keypad Backlight Chip and Diagram
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Keypad Backlight Display Phoenix Interface
Run the Display Test in Phoenix to check the keypad backlight.
Turn on Dlight
Turn on Klight
GPS
How GPS Works
This is a 911 GPS service only. This means that when you dial 911, the GPS turns on by
using Vcore from the external DC-DC and VIO from UEMEK. GPS communicates with
D2800 using the UART interface. This turns on the BB chip and the RF chip. They
Figure 27: Phoenix Display Test option
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Baseband Description and Troubleshooting
synchronize with the phone using the 19.2Mhz clock. The phone locates the closest
satellite and downloads the location coordinates to send them to the Emergency desk.
Figure 28: GPS Block Diagram
GPS Troubleshooting
When troubleshooting GPS, make these common checks (see Figure 29 and Figure 30):
• Check the Power Vcore and VIO
• Check that GPS_RF_CLk = 19.2Mhz
• Check the GPS_EN_Reset
• Check that Sleep_CLK = 32.768kHz
• Check that VRF_GPS = 2.78
• Check that the GPS clock = 16.384Mhz
• Run Test Mode 1 on Phoenix
• Check USART activity
• Check SPI activity
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• Check RF Data and Clk activity
Figure 29: GPS Power VCore or VIO
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VREF_GPS
GPS_CLK
VCore (1.57V)
VIO (1.8V)
VDD_1O_GPS
GPS_U2TX
GPS_U2RX
GPS_Sleepx
GPS_Sleep_Clk
GPS_UI_RX
GPS_UI_TX
GPS_INT_UI_CLK
GPS_UI_DATA-RDY
GPS_RF_CLK
GPS_EN_RESET
Figure 30: GPS Chip
GPS_SPI_EN
GPS_SPI_DATA
GPS_SPI_CLK
GPS_B3
GPS_B2
GPS_B1
GPS_B0
GPS_CLK
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GPS Phoenix Interface
Run the GPS Quick Test in Phoenix to check the GPS BB.
CW test fails unless CW tone is injected
in GPS RF connector
SIM Card
How SIM Card Works
Nokia 6235/6235i/6236i supports two types of SIM cards that work at 1.8V and 3.0V.
When you power up your phone with a SIM card, D2800 sends a 1.8V signal to the SIM
card and waits for the SIM card’s response and identification. After a wait period, if there
is no answer from the SIM card, the phone will send another signal at 1.8V. In this case
Figure 31: Phoenix GPS Testing option
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Baseband Description and Troubleshooting
UEMEK acts as a level shifter and raises the signal to 3.0V. If there is still no response,
the phone does not allow access. If there is a response, then phone powers up.
SIM Card Troubleshooting
When troubleshooting SIM cards, make these common checks (see Figure 29 and
Figure 30):
Figure 32: SIM Card Block Diagram
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• Check Vsim 1.8V or 3.0V. Vsim comes from UEMEK and goes through the SIM ESD
Protection chip. Check for bad or damaged solder joints. Replace chips, if
necessary.
Figure 33: Vsim check
• Check Detection sequence
VSIM
GND
SIMRSTX SIM_CLK
SIM_CLK
SIM_IOX
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Figure 34: Detection sequence
• Verify communication signals
Figure 35: Commuication signals
• If no signals are present: (1) check contacts on Sim Connector are correct, (2)
check ESD Chips are correct, and (3) check UEMEK are correct. Replace damaged
parts, if necessary.
SIM Connector
SIM ESD
Protection
Figure 36: Vsim check
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Sim Card Phoenix Interface
Run the SIM-Lock Status in Phoenix to test a SIM (or RUIM) card.
Infrared
How Infrared Works
D2800 enables the infrared (IR) module by switching high GenIO (23). The UEMEK
provides two power supplies to the infrared module: VIO for digital Logic and Vflash1 for
Figure 37: Phoenix SIM Testing options
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Baseband Description and Troubleshooting
infrared supply. The Vbat powers up the IR LED. This interface receives data from and
transmits data to peripheral equipment through the IrRX and IrTX line.
Infrared Troubleshooting
When troubleshooting infrared, make these common checks (see Figure 39):
• Performed a good visual inspection on infrared module and caps
• Check for power supplies VIO, Vflash1, and Vbat
• If VIO and VFlash1 is not correct, check UEMEK
• Check GenIO(23) is enable high
• Check for activity on IRTX and IRRX line,when transmitting or receiving
• If GenIO(23) or IRTX and IRRX are not working, check D2800
Figure 38: Infrared Block Diagram
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IR Module
Infrared Phoenix Interface
Run the IR Test in Phoenix to test infrared.
GND
VIO
VFlash1
GENIO(23)
IRRX
IRTX
Vbat
Figure 39: Infrared Chip and Diagram
Figure 40: Phoenix IR Test options
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Baseband Description and Troubleshooting
System Connector
Figure 41 provides a mapping for the system connetor.
Figure 41: System Connector
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Accessory Detection
Figure 42 provides a diagram that display how the phone detects accessories. Dummy
accessories pull down to GND ACI Line. Smart accessories pull down ACI line with a 56K
Ohm resistor allowing communication between accessory and UEMEK.
VFlash1 (2.78V)
VAUX2 (2.78V)
Smart accessories detection
Figure 42: Accessory Detection Diagram
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Baseband Description and Troubleshooting
Battery (Lynx) Interface Circuit
Figure 43 provides a diagram of the battery interface circuit. The BSI voltage level for the
normal mode is 1.23V, for the test mode is 170MV, and for the local mode is 90MV.
BSI voltage level
Figure 43: Battery Interface Circuit
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PWB Overview
Bottom Board
Figure 44: PWB - Bottom
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Top Board
Figure 45: PWB - Top
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Main Test Points
Current Test Points
VSIM
VR5
Current too High at Zero Test
Check the following points, if the current is too high at zero (see Figure 46 and
Figure 47):
VFlash1
VANA
VAUX
Figure 46: Current Test Points
VR3
VR7
VR6
VR4
VCOREIn
VR2
VR1A
VR1B
VBATbb
1. Is the VBAT contact intact?
2. Measure BB regulator voltage levels:
• VANA—2.78V
•VIO—1.8V
• VCORE—1.35V/1.05V @ Sleep
• VFlash1—2.78V
• VR3—2.78V
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Baseband Description and Troubleshooting
3. Is System clock at 19.2MHz
4. Is Sleep Clock at 32kHz
5. If all the above checks pass, then check whether terminal is jammed or a flash
fault exists.
R2206
BSIGND
VBAT
X2000
R2203
Sleep Clock
Figure 47: Test Points when current too high
Terminal in Local Mode Test
Check the following points, to see if terminal is in local mode (see Figure 47):
1. Is the BSI line at X2000?
2. Is the BSI line at R2203?
3. Is the BSI line at R2206?
4. Is Sleep Clock at 32kHz?
5. Is System Clock at 19.2kHz
System Clock
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Nokia Customer Care Baseband Description and Troubleshooting
Display Test
Check the following points for the display (see Figure 47):
1. Is the VBAT voltage at X2000?
2. Is the VBAT voltage at C2000?
3. Is the BSI line at R2206?
4. Is the BSI line at R2203?
5. Is Sleep Clock at 32kHz?
6. Is System Clock at 19.2kHz
Charging Test
Check the following points, charging (see Figure 48):
1. Does the battery bar scoll work?
2. Measure the BTEMP at V2000, check if it is at 25 degrees C. If not, replace the
UEM.
3. Remove fuse at F2000 and measure current, check if it is at 850mA. If not,
replace the UEM.
4. Measure the voltage at V2000, check if it is at 3VDC.
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Baseband Description and Troubleshooting
UEME
Battery Bar Scroll
F2000
V2000
Figure 48: Charging Checks
Common Problems
The following section has a list of common problems, along with some standard checks.
No Communication During Flash
• Make sure good connection between flash adaptor and phone
• Phone has to be powered by prommer (FPS-8)
• Check Baseband regulators VR3, VIO, VCORE, VFLASH1
• Phone will not able to flash without 19.2Mhz clock into UPP
• Check BSI, MBUS, FBUSRx, FBUSTx, PURX, SLEEPX for bad solder joints between
UEM and UPP
• Check Flash bus signal and VPP voltage level
No Communication During Alignment
• Check all connection between test fixture, cables and phone
• Make sure phone is in Local Mode check BSI signal level if not
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Nokia Customer Care Baseband Description and Troubleshooting
• Make sure phone was programmed/flashed
Failed Self Test/Calibrate
• Make sure phone is in local mode
• Make sure power supply provides enough current (usually approximately 500mA
and 2A for tuning)
• Use the troubleshooting guide’s float chart to verify the failed circuit
• Check the signals and voltage levels per troubleshooting guide.
Phone Not Powering Up
Refers to when no power causes phone to not able to flash, not to get into local mode
and similar problems.
• Check baseband regulators – VR3, VIO, VFLASH1, VCORE dc/dc, PURX
• Check VCTCXO 19.2MHz signal at UPP input
• Check power up sequence
• Check Flash IC, flash bus signals, and voltage level
Shut Down After 32 Seconds
• Check for the absence of 32KHz SleepCLK
• Check for incorrect SleepX and PURX signal levels
• Check if ESN number was corrupted
No Audio
• Check for bad contacts or damaged earpiece
• Check for bad connections at mic
• Check for broken or bad solder joint of passive components
• Verify the audio signal paths using BaseBand “audio test” component with
Phoenix as described in the troubleshooting guide
Key Pads Malfunction
• Check for protective film left on back of the key dome if a new one was installed
• Check for corrosion on both the key pads and key dome
• Check if flash software was corrupted
• Check for bad joint from UPP to Interface
• Check for pins shorted on or bad on Z300
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Baseband Description and Troubleshooting
No LCD Display
• Check for bad connections
• Check for a cracked or damaged display
• Probe test points as described in the troubleshooting guide for missing for
incorrect signal level
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