NOKIA NSE8-037 free download

File name NSE8-037.PDF

CONFIDENTIAL 1 (1) Nokia Mobile Phones Service Bulletin No. SB-037/20.04.00 Technical Support, Europe & Africa NSE-8 COBBA UNDERFILLING In some cases when NSE-8 is exposed to mechanical stress (dropped etc) WKH &2%%$ %*$ FRPSRQHQW 1 PD\ VXIIHU IURP FUDFNV EHWZHHQ WKH solder-balls and the pads on the PCB. Typical symptoms are dropping calls, loosing service or signal indicator is unstable on the display. As underfilling for COBBA is solution for those cases it has been taken in use in production since IMEI: 449143/10/716000/x. Note: It is not possible to rework or replace an underfilled COBBA %*$ FRPSRQHQW In case of phones without underfilling of COBBA: 1. 5HPRYH WKH &2%%$ %*$ XVLQJ D %*$ &63 UHZRUN VWDWLRQ 2. Inspect the number of oxidised pads "black pads" on the PCB under COBBA (dark coloured pads). If there are more than 6 black pads then scrap the PCB. Less than 7 black pads will ensure high reliability of reworked component. 3. Remove carefully excessive solder from the COBBA solder pads 4. Apply flux to the COBBA solder pads (use a strong no-clean flux to remove oxides) 5. Mount a new &2%%$ FRGH  XVLQJ D %*$ UHZRUN VWDWLRQ 'R not mount the removed COBBA!!) 6. Re-build the phone IMEI and re-initialise the SIM locks 7. Test and tune the phone's RF performance (COBBA stores RF A/D values) NSE-8 SB-037