3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting Power Up Sequence When the mobile terminal 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...
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting Figure 2: Measured power-on sequence and timing Flash Programming Flash Programming Flashing Tool Flash programming is done through the VPP, FBUSTX, FBUSRX, MBUS, and BSI signals BSI = Used to indicate to MCU that the prommer is connected and mobile terminal is in...
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting Figure 3 shows the DA-47 flashing tool and Module Jig MJ-57. Figure 3: DA-54 Flashing Tool and MJ-57 Module Jig Flashing Troubleshooting When troubleshooting flashing problems, first make sure the signals from the FPS-8 to the D2800 processor are functioning properly before replacing any component.
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3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting • When flashing or erasing the mobile terminal, monitor the MBUSRX and FBUSRX signals from the UEMEK to the D2800 processor for a signal at these points. If either signal does not appear, check the signal at the production test points. If the signal is ok, check the UEMEK.
• MIC3 input is used for the Universal Headset Every microphone input can have either a differential or single-ended AC connection to the UEMEK circuit. In the Nokia 3155/3155i/3152, the internal microphone (MIC1) and external microphone (MIC2) for Pop-Port™ accessory detection are both differential.
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting Audio Troubleshooting When troubleshooting the audio, make these common checks (see Figure • Perform visual inspection of all the ASIPs and the UEMEK. • Inject 1KHz signal into MiC1 and trace it to the earpiece. Only when using IHF signal will be amplified by a factor of 8.
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting Audio Phoenix Interface Run Audio Test in Phoenix to check the audio functionality. MiC1 - Use the first option to route the audio from the internal microphone to the headset speaker.
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting FM Radio How the FM Radio Works The D2800 turns on the FM radio and sets the frequency using the CBUS serial interface as the communication channel. A high frequency FM radio signal comes in through RFIN1 Pin to the FM radio chip and gets demodulated into a low frequency signal and is sent to the UEMEK for amplification.
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting • If the audio signal not correct (with 800mv DC-offset), then check FM radio chip for shorts, voids, and misalignments • If the audio signal is correct (with 800mv DC-offset), then check the UEMEK for shorts, voids, and misalignments •...
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting USB (Universal Serial Bus) How the USB Interface Works When the mobile terminal is connected 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 mobile terminal will respond by pulling the D+ line high.
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting USB Troubleshooting First connect mobile terminal to the computer using a DKU-2 data cable. Check under device manager if the computer recognizes the mobile terminal as a USB device. If the mobile terminal is recognized, there is no hardware fault and you can stop troubleshooting.
Display How the Display Works Nokia 3155/3155i/3152 has a large main display (160 x 130 color depth), controlled by the D2800 engine through a parallel interface. The secondary, black and white display (96 x 68) is controlled by the D2800 engine through a serial interface. The UEMEK powers using VIO and VFlash1.
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting Secondary display connection V Flash 1 DIFF_ DA3 LCD_CSX DIF_WRX LCD_CLK DIF_RDX LCD_ DA DIF_CLK Main display connection Figure 19: Display Chips and Frequency Display Backlight Troubleshooting When troubleshooting the display backlight, make these common checks (see...
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3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting • Check Klight is enabled high (~4V) for main LCD and keypad LEDs. If not correct, check UEMEK. • Check Vbat(~4V) and Vin(~4V) are present on driver inputs. If not, check power supply connection.
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting Keypad Backlight How the Keypad Backlight Works Klight coming out of UEMEK controls the keypad backlight LEDs. Klight enables the LED driver, which is a constant voltage supply for all the keypad LED in series. The current is set for all the branches by Rset which in this case is 33k Ohms and equates to 10mA through each LED.
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting How GPS Works This is for emergency 911 GPS service only. When you dial 911, the GPS turns on by using Vcore_Lin and VIO from UEMEK. GPS communicates with the D2800 using the UART interface.
UIM Card How the UIM Card Works The Nokia 3155/3155i/3152 supports two types of UIM cards that work at 1.8V and 3.0V. When the mobile terminal is switched on with a UIM card, the D2800 sends a 1.8V signal to the UIM card and waits for the UIM card’s response and identification. After a wait period, if there is no answer from the UIM card, the mobile terminal will send another signal at 1.8V.
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3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting • Verify communication signals Figure 32: Commuication signals • If no signals are present: (1) check contacts on Sim connector are correct, (2) check ESD chips are correct, and (3) check the UEMEK is correct. Replace damaged parts if necessary.
Baseband Description and Troubleshooting System Connector Figure 35 provides a mapping for the system connetor. The 3155/3155i/3152 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).
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting Accessory Detection Figure 36 displays how the mobile terminal 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.
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting Battery (Lynx) Interface Circuit Figure 37 illustrates the battery interface circuit. The BSI voltage level for different power-up modes: • normal mode - 1.23V • for the test mode - 170MV •...
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting Charging When troubleshooting battery charging, make these common checks (see Figure Figure 39 Figure 40): • Does the battery bar scroll? Battery level indicator Figure 38: Battery indicator bar • Measure voltage at V2000. Is it >3VDC? Figure 39: Charging layout •...
3155/3155i (RM-41), 3152 (RM-61) Nokia Customer Care Baseband Description and Troubleshooting Common Problems The following section has a list of common problems, along with some standard checks. No Communication During Flash • Make sure there is a good connection between flash adaptor and the mobile terminal •...
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting 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...
3155/3155i (RM-41), 3152 (RM-61) Baseband Description and Troubleshooting Nokia Customer Care Main PWB Overview Test point map - bottom VANA VR6 VR2 VCORE VR1A VR1B VFLASH2 VFLASH1 UEMEK 32 KHz Crystal Memory Flash 256 Meg SIM DATA SIM RESET VSIM...