Nokia Customer Care 6255/6255i6256/6256i (RM-19) Mobile Terminal Baseband Description and Troubleshooting Issue 2 05/2005 Company Confidential ©2005 Nokia Corporation
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Contents Page Introduction ..................................................................................................................................................... 4 Power Up and Reset .................................................................................................................................... 6 Power Up - Power Key.................................................................
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Secondary Display Test Points.................................................................................................................. 45 GPS Module .................................................................................................................................................48 Troubleshooting...................................................................................................
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care This page intentionally left blank.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Introduction The 6255/6255i/6256/6256i baseband module is a tri-mode, Code Division Multiple Access (CDMA), dual-band engine and is based on the DCT4.5 standard.
255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Battery Sim Production Test IF Zocus Nokia Customer Care MMC Regulator 32 KHz Mic UEME IHF Speaker Amplifier UHS Jack Regulation DC Jack Charge Control EarPiece Audio Nut Tomahawk USB Vibra FBUS / MBUS SIM I/F Disp BL’s CBUS RTC PWM VIO Antenna RF Bluetooth Cam Flash D B U S Int Display Tiku EDGE GPS PWM Parallel PCM / UART UART 19.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Power Up and Reset The UEME ASIC controls the power up and resets.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Reference signal PwrOnX Charger Detection RTC Reset mode is entered and the watchdog starts UEMRSTX VCORE End of settling time (only if Vbat > Vcoff+_); VFLASH1 regulator enabled VFlash1 VIO VANA VR3 19.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Figure 3: Measured power-on sequence and timing Power Up - Power Key When the power key is pressed, the UEME enters the power-up sequence. Pressing the power key grounds the PWRONX pin on the UEME. The UEME PWRONX signal is not part of the keypad matrix. The power key is only connected to the UEME. When the power key is pressed, an interrupt is generated to the D2800 processor that starts the MCU.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care 100mA of constant output current from the connected charger’s output voltage. The battery’s voltage rises at it charges, and when the VBAT voltage level is detected to be higher than master reset threshold limit (VMSTR+), the start-up charge is terminated. When VBAT is greater than VMSTR+, the Master Output Reset (MSTRX) signal, which is internal to the UEME, is set to a Logic 1.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Sleep Mode When the SLEEPX signal is detected low by the UEME, the mobile terminal enters sleep mode. In sleep mode, both processors (MCU and DSP) are in stand-by mode. The mobile terminal enters sleep mode only when both processors make this request.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care The charging control circuitry (CHACON) inside the UEME controls the charging current delivered from the charger to the battery. The battery voltage rise is limited by turning the UEME switch off when the battery voltage has reached 4.2V. The charging current is monitored by measuring the voltage drop across a 220mOhm resistor.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Table 3 includes the UEME RF regulators. Table 3: RF Regulators Regulator Maximum Current (mA) Vout (V) Notes VR1A 10 4.75 Enabled when cell receiver is on VR1B 10 4.75 Enabled when the transmitter is on VR2 100 2.78 Enabled when the transmitter is on VR3 20 2.78 Enabled when SleepX is high VR4 50 2.78 Enabled when the receiver is on VR5 50 2.78 Enabled when the receiver is on VR6 50 2.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Clock Distribution RFClk (19.2MHz Analog) The main clock signal for the baseband is generated from the voltage-controlled temperature-controlled crystal oscillator (VCTCXO). This 19.2MHz clock signal is generated by the radio frequency circuitry and fed to the radio frequency clock (RFCLK) pin of the D2800 processor. The 19.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting RFConvClk (19.2MHz Digital) The D2800 processor distributes the 19.2MHz clock to the internal processors (the DSP and MCU) where the software multiplies this clock by seven (=134.4MHz) for the DSP and by two (=38.4MHz) for the MCU.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care CBUSClk Interface CBUS utilizes a 1.2MHz clock signal, which is used by the MCU to transfer data between the UEME and the D2800 processor.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting DBUS Clk Interface DBUS utilizes a 9.6MHz clock signal, which is used by the DSP to transfer data between the UEME and the D2800 processor.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care SleepCLK (Digital) The UEME provides a 32kHz sleep clock for internal use and also to the D2800 processor, where it is used for the sleep-mode timing.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting SleepCLK (Analog) When the system enters sleep mode or power-off mode, the external 32KHz crystal provides a reference to the UEME. The RTC circuit also uses this clock to turn on the mobile terminal during power-off or sleep mode.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Flash Programming Indication After connecting the flash prommer to the mobile terminal, the flash prommer sets the MBUS line low to notify the MCU that the flash prommer is connected. This causes the UEME reset state machine to perform a reset to the system by setting the PURX signal low for 20ms.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting FLASH_1 CH1 = BSI CH2 = MBUS CH3 = FBUSTX CH4 = FBUSRX Measure points Production test pattern (J396) Figure 10: Flashing starts by BSI being pulled up and password being sent to UEME This boot code asks the MCU to report the mobile terminal’s configuration information to the prommer, including the flash device type.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care FLASH_2 CH1 CH2 CH3 CH4 = = = = PURX MBUS FBUSTX FBUSRX M easure points Production test pattern (J396) Figure 11: Flashing, continued Page 22 • Ch1= PURX • Ch2 = MBUS toggled three times for MCU initialization • Ch3 = FBUS_TX low, MCU indicates that prommer has been noticed • Ch4 = FBUS_RX ©2005 Nokia Corporation Company Confidential Issue 2 05/2005
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting FLASH_3 CH1 CH2 CH3 CH4 = = = = PURX MBUS FBUSTX FBUSRX M easure points Production test pattern (J396) Data transfer has started (Fbus_Rx) Figure 12: Flashing, continued 2 Flash Programming Error Codes The following characteristics apply to the information in Table 4. • Error codes can be seen from the test results or from Phoenix's flash-tool.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Table 4: Flash Programming Error Codes (Continued) Error Description Not Working Properly C103 " Boot serial line fail." Mbus from Prommer->UEME>UPP(MbusRx)(SA1) FbusRx from Prommer->UEME->UPP FbusTx from UPP->UEME->Prommer C104 "MCU ID message sending failed in the Phone." FbusTx from UPP->UEME->Prommer C105 "The Phone has not received Secondary boot codes length bytes correctly.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Charging Operation Battery The mobile terminal uses a Lithium-Ion cell battery (BL-6C) with a capacity of 1070mAh. Reading a resistor inside the battery pack on the BSI line indicates the battery size. An NTC resistor close to the SIM connector measures the mobile terminal’s temperature on the BTEMP line. Temperature and capacity information are needed for charge control.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Charger Detection Connecting a charger creates voltage on the VCHAR input of the UEME. Charging starts when the UEME detects the VCHAR input voltage level above 2 V (VCHdet+ threshold). The VCHARDET signal is generated to indicate the presence of the charger for the SW. The EM SW controls the charger identification/acceptance.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Main Display There are three LEDs for the main display, which utilize the KLIGHT signal. Table 5 shows the characteristics of the main display.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Secondary Display There are three LEDs for the secondary display, which utilize the DLIGHT signal. Table 5 shows the characteristics of the secondary display.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care DC Measurements Table 7: Power Supply Characteristics Signal Name Measured Value (V) Min Typical Max Unit Description VIO 1.8 1.7 1.8 1.9 V Control line VANA (Vflash2) 2.79 2.7 2.78 2.9 V Analogue supply VDIG 1.79 1.7 1.8 1.9 V Digital supply GND 0 V System GND 0 Table 8: DC Characteristics Measured Value (V) Min CSX H = 1.80 L = 2.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care FM Radio FM radio circuitry is implemented using highly integrated radio IC, TEA5767HN. FM radio circuitry is controlled through the serial bus (GenIOs) interface from MCU SW. Figure 18: FM Radio (N356), Audio (N150), antenna, and digital interface connections Stereo audio output signals are fed to the stereo amplifier. Volume control of the FM audio signal is made by circuitry inside the amplifier.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Figure 19: FM Radio signals before Radio on • Ch1 : FMClk(32.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Figure 20: FM Radio signals after Radio on USB Interface The USB (Universal Serial Bus) allows up to 127 devices to be attached via a tree-like structure of hubs and devices all emanating from one root host. Devices can be attached or detached at any time without concern for rebooting the PC or loading device driver software. Detection of attachment or detachment is done automatically and requires no user input.
6255/6255i6256/6256i (RM-19) Nokia Customer Care Baseband Description and Troubleshooting UEME TIKUEdge VAUX3 ARM MCU Genio # NUT_Fbus NUT_speed Genio # VIO Vreg NUT SEmode _Speed VIO USB ASIP W2FC PVCI Bus, IRQs, DMA control System Vctcxo 48MHz DPLL Genio # PUENO USBOEx GZO CLK48I System Connector 10K USBRCV RXDI USBVM RXDMI RXDPI SE0O TXDO USBVP_FRX USBFSE0_FTX SUSPENDO USBVO Genio # 3.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care The USB consists of four signals: Table 10: USB Signals Signal Description Vbus 5V Power supply from host to device D+ Differential data signal (swings between 0 and +3.3V) D- Differential data signal (swings between 0 and +3.3V) GND Ties host and device ground together When the mobile terminal is attached to a USB host, the host provides a 5V supply at the Vbus pin of the system connector.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Accessories The 6255/6255i/6256/6256i supports Pop-port and Universal Headset accessories, differential and single-ended, respectively. Detection of the Pop-port accessories is done through the ACI signal where the Universal Headset is detected on TIKU_GenIO (4).
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Charging Charging through Pop-port is accomplished in the same manner as through the charger connector. Pin 1 of the Pop-port is physically connected to the charger connector. When the mobile terminal is connected to a desktop charger (e.g., DCV-15), it charges in the same manner as it does with the charger connector. Figure 23 shows the actual charging sequence.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Pop-port Headset Detection Accessory detection on the Pop-port is done digitally.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Figure 25: Waveform showing Pop-port FBus communication Accessory Detection Through ACI USB and Audio on (mono or stereo)/FM radio communication in Pop-port is done through the following signals: Table 12: Accessory Detection Signals USB Audio/FM Pin 5 (USB Vbus) Pin 9 (XMic N) Pin 6 (USB +) Pin 10 (SMIC P) Pin 7 (USB -) Pin 11 (HSEAR N) Pin 8 (Data GND) Pin 12 (HSEAR P) Pin 13 (HSEAR R N) Pin 14 (HSEAR R
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Figure 26: Waveform showing accessory detection through ACI Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 39
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care RUIM (SIM CAR) The 6255/6255i/6256/6256i supports SIM CAR. Use the waveform in Figure 27 to verify that the sim_vcc, sim_i/o, cim_clk, and sim_rst signals are activated in the correct sequence at power up. This picture may be taken when the SIM CAR is installed on the mobile terminal to measure the signals when the mobile terminal is turned on. The figure shows the proper waveforms when the interface is working.
6255/6255i6256/6256i (RM-19) Nokia Customer Care Baseband Description and Troubleshooting Main Display Test Points SLEEP_CLK CBUS_EN CBUS_DA VBAT MICB1 CBUS_CLK BSI GND MICB2 RFBUS_CLK PURX Figure 28: Main display test points - top Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 41
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Vibra SIMDAO SIMCLKO SIMRST SLEEPX VSIM VIO VFLASH1 MMC card Figure 29: Main display test points - bottom - 1 Page 42 ©2005 Nokia Corporation Company Confidential Issue 2 05/2005
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care 19.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care POWERON_X Flex connector LCDCAM_CLK Figure 31: Main display test points - bottom - 3 Page 44 ©2005 Nokia Corporation Company Confidential Issue 2 05/2005
6255/6255i6256/6256i (RM-19) Nokia Customer Care Baseband Description and Troubleshooting Secondary Display Test Points GPS_U2TX VIO GPS_U2RX V LED + GND Earpiece_1 Earpiece_2 Secondary display Secondary display driver enable Figure 32: Secondary display test points - top Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 45
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting CAM_LED_EN Nokia Customer Care 19.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care VFLASH_LIGHT Camera flash driver VBAT LED driver Camera Figure 34: Secondary display test points - bottom - 2 Issue 2 05/2005 ©2005 Nokia Corporation Company Confidential Page 47
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care GPS Module The GPS circuitry utilizes RF signals from satellites stationed in geosynchronous orbit to determine longitude and latitude of the handset. The GPS circuitry is completely separate of the CE circuitry and is located almost exclusively on the secondary side of the PWB underneath the display module. Figure 35: GPS Block Diagram Use the following steps for basic GPS BB troubleshooting: 1.
Nokia Customer Care 6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Troubleshooting The following hints allow you to find the cause of the problem when the circuitry seems to be faulty.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Mobile Terminal is Totally Dead Mobile terminal is dead Mobile termninal current is zero or too high? ¾ If current is zero, check X2002 to make sure Vbat makes contact. ¾ If current is too high, check for shorts. ¾ Make sure all BB regulators are at their respective voltage levels (VANA, VIO, VCORE, VFlash1, and VR3). See phone's top view diagram for test points. ¾ Make sure the system Clk is 19.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Flash Programming Does Not Work Flash faults The mobile terminal does not set Flashbus TXD line high after the startup YES Measure BSI pulse during Flash programming. Is it OK? NO Check BSI line X2002, C2015, R2202, R2205 NO Reflow or change UEM YES Measure FBusRXO (2.78V) signal during flash programming from production pattern and FBUSRX test point (1.8V).
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Flash Faults Page 2 Can you read the manufacturer ID and the device ID? NO Re-flow the flash. Is it OK? NO Re-flow the UPP.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Power Does Not Stay on or the Mobile Terminal is Jammed Check VBATT, VIO, VCORE, VFlash1, VANA, VR3 capacitors. Are they OK? Mobile terminal is jammed NO Measure VIO, VCORE, VFlash1, VANA, and VR3 voltages. Are they OK? NO Repair NO Change B2200 NO Check G7200, R7200, C7200, C7203, R7205, and C7207. NO Repair NO Change UEM NO Change UPP YES Check BSI/BTEMP lines and VBATT lines.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Mobile terminal is jammed, page 2 Mobile terminal shutdown after 32 seconds Has the mobile terminal been flashed? YES NO YES Measure DBusClk (9.6 MHz), Data, and EnX signals. Are they OK? NO YES Reflow or change UPP. Read mobile terminal info. Is it OK? YES Retest Flash the mobile terminal NO NO Measure watchdog signal Cbus. Is it OK? NO Reflow or change UEM and reflash.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Charger Faults Charger faults Connect Charger. Make sure battery is connected. Battery bar doesn't work (scroll) NO Retest NO Check X2001, F2000, L2006, V2000, C2012, and C2013. NO Change UEM NO Change UEM YES Measure voltage over V2000. Is it >3.0 Vdc? YES Read BTEMP value. Is it ~25C? YES Remove (fuse) F100 and measure current with an ACP9 charger.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Audio Faults Earpiece A udio faults Is the earpiece w orking? NO C hange earpiece. Is it w orking now ? YES R etest NO Set phone in Local M ode. U se Phoenix Troubleshooting > Phone C ontrol > Phone State tab > Select Local M ode > click Execute. Then use A utio Test > H P m icrophone in/H P speaker out > Loop O N to enable earpiece. Inject a 1K H z sine signal 200Vp-p on XM IC .
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Microphone Audio faults, page 2 Is the microphone working? NO Change the microphone. Is it working now? YES Retest NO Set mobile terminal in Local Mode. Use Phoenix Troubleshooting > Phone Control > Aphone State Tab > select Local Mode > click Execute. Then use Audio test > HP microphone in/HP speaker out > Loop ON to enable the earpiece. Talk through the microphone.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care IHF Audio faults, page 3 Is IHF working? NO Check IHF audio amplifier (N2100). Is it OK? NO Replace N2100. YES YES Set the phone to Local Mode. Use Phoenix to open Troubleshooting > Phone Control > Phone State tab > select Local Mode > click Execute. Then use Audio test > HP microphone in/ Ext speaker out > Loop ON. Measure and check IHF test points IHFA and IHFB. Are they OK? NO Check R117, R2118, R2119.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Vibra A udio faults, page 4 Is Vibra w orking? NO M easure VB A TT voltage pin 1 of M 2400. Is it O K ? NO C heck VB A TT line Y ES U se the U I M enu > Profile > N orm al > C ustom ize > Vibrating A lert > S elect O n > then go back to C ustom ize M enu > R inging Tone > Try any ring tone. D oes the vibra w ork? YES Y ES M easure the U EM signal on pin 2 of M 2400.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Display Faults Main Display Main Display faults Are the UI module and display LEDs turned on when the mobile terminal is turned on or when making a call? NO Measure KLIGHT at R2455, Vbat at C2451, and Pout at C2453. Are they OK? NO If Vbat is not OK, check the battery. If Pout is not OK, check N2450. NO Replace NO Replace NO Change UEM NO Replace display module. YES Measure test point X2453 (~>12).
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Main Display faults, page 2 Does the Display show an image? NO Try changing display module. Is it OK? YES Retest NO Change UEM NO Measure VIO and VFLASH1. Is it OK? YES Check LCD signals LCDCSX, LCDCLK, LCDDA, and XRES. Are the signals OK? (Refer to the display section.
55/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Secondary Display Secondary Display faults Are the secondary display LEDs on? NO Check N2451. Is it OK? NO Replace the N2451. NO Check Vbat connector and battery. NO Replace LEDs. NO Replace NO Replace the UEM. YES Check Vbat at C2470. Is it OK? YES Check V2450, V2451, and V2452. Are they OK? YES YES Check C2468, C2469, and R2457. Are they OK? YES Check DLIGHT.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Keypad Faults Power Key Keypad faults Is the power key working? NO Measure voltage at pin 1 and 3 (S300). Is it high? NO Check S300, C314, and R304. If OK, change UEM YES YES Measure voltage at pin 1 and 3 (S300) when the power key is pressed. Is it high? YES Check S300.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care UI Modules Keypad faults, page 2 Are UI modules keys working? NO Change keypads module. Is it working? YES Retest NO Measure ROW0-4 Keyb(5) and Keyb(9) signals between UPP and Z2400. Are they ~1.8V? YES YES Retest NO Make sure there are no shorts on Z2400. Is it OK? YES Change the UPP.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care EL Panel and Driver EL Panel and Driver Faults Is the keypad backlight on? NO Check Tiku_GPIO(57). Is it OK? NO Replace D2800 NO Replace N2400 YES YES Check N2400. Is it OK? YES Is the root EL power 180Vpf-pk? EL Panel OK YES Check EL panel.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care USB Before proceeding with the USB faults troubleshooting portion of this guide, attach a DKU-2 cable between the mobile terminal and the PC. The PC must recognize that a USB device has been attached and load driver(s) for that device. The mobile terminal appears in the Device Manager dialog box.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care If no device is detected, proceed as follows: USB faults Check continuity between system connector pin 5 and R1053 NO Replace system connector NO Replace system connector NO Replace system connector NO Replace system connector YES Check continuity between system connector pin 6 and R1054 YES Check continuity between system connector pin 7 and R1055 YES Check continuity between system connector pin 8 a
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care USB faults page 2 Attach DKU-2 cable between PC and phone YES Check for ~5V on C1022 NO Check for ~5V on Z101 NO USB host not supplying VBUS, check connection to PC NO Replace NUT and check for ~2.8V on R1187 YES YES Check for ~2.8V on pin 6 of system connector Replace R1190 NO Check for ~2.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care USB faults page 3 Check for ~0V on pin 7 of system connector NO Check for ~0V on J960 NO Replace NUT and check for ~0V on J960 YES YES YES Hardware functioning properly Replace USB ASIP Retest Issue 2 05/2005 ©2005 Nokia Corporation NO Company Confidential Replace D2800 Page 69
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care MMC The hardware of the MMC interface from the UEME (D2200) to the MMC connector (X3200) cannot be tested without an MMC card. Solder wires on respective points to be able to measure the following. MMC faults Measure VBAT at C3200 = 3.7-4.2V? NO Defective PWB NO Replace N3200 NO Resolder X3200 NO Replace R3202 YES The following points can be measured at phone power up because the MMC is initialized here.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care FM Radio FM Radio faults Is the FM radio working? NO Power on the phone and turn FM radio on by Phoenix NO Check solder on N6100, X101, and replace N6100 if not working. YES Measure VFlash2 (VCCD/VCCA/ VCCVCO) at C6103/ C6116/C6117/L6101. Is it 2.8V? YES Measure FM1=1.8V, FM2=11 Khz, FM3=1.8V, and FM4=32 Khz. Is it OK? YES NO Check VFlash2 line Measure FMANT at L6103. Is it 1.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care (To Radio Faults 1) FM Radio faults 2 Measure VREF at C6106. Is it 1.6V? NO Check C6106 NO Change FM Radio chip (N6100) YES Measure VAFL/VAFR at C6180/C6182.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care Camera Camera faults Power on the phone and turn camera on by Phoenix or UI menu NO Make sure soldering on D6600 and X6600 is OK and check PUSL(1) on pin 19 of X2451.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care The error "SIM card rejected" means that the ATR message received from the SIM card is corrupted (e.g., data signal levels are wrong). The first data is always ATR, and it is sent from the card to the mobile terminal. SIM faults Is the SIM a 3.0V or 1.8V card? NO Replace used test SIM card NO Check SIM reader X2700 YES Measure VSIM at X2700 pin 3. Is it 3V or 1.8V? NO YES Check SIM power-up sequence.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care GPS GPS faults Is VCORE at 1.5V? NO Troubleshoot CE power supply YES NO Is VIO at 1.8V? YES GPS_RF_CLK (19.2MHz) OK? NO Troubleshoot CE VCTCXO circuit NO If the BB ASIC is being held in reset, troubleshoot the source in the CE NO Troubleshoot CE sleep clock circuit NO VRF_GPS regulator enable line low? YES GPS_EN_RESET held high? YES GPS_SLEEPCLK (32.
6255/6255i6256/6256i (RM-19) Baseband Description and Troubleshooting Nokia Customer Care This page intentionally left blank.
