Phone Is Totally Dead; Flash Programming Fails - Nokia NSB-7 Series Service Manual

NSB-7
Disassembly & Troubleshooting
Ch4 = PURX (see picture B)
CUAd1
MCUWrX
MBUS

Phone is totally dead

The phone doesn't take current at all when the power switch is pressed or when the
watchdog disable pin (X001 pin 11) is grounded. Make sure that the battery voltage you
use is within the specification, i.e. 3.11.. 4.2 V. If the voltage is lower, hardware of CCONT
(N100) prevents power on.
IF battery voltage is inside the specification Change the CCONT.

Flash programming fails

The flash programming can be done via panel connector X001 or via dedicated PCB pads.
In production, the first programming is done via panel connector. After this, the panel
connector is cut away, thus the programming must be done via PCB pads visible through
the shield under the battery. The main difference between these is that FLASH-program-
ming voltage is produced differently. The fault finding diagrams for flash programming is
shown in the start up sequence picture.
Page 28
B
FBUSRx
ROM1SelX
MCURdX
ãNokia Mobile Phones Ltd.
PAMS Technical Documentation
Xf
CLK 32 kHz
PURX
Ccont int.
VXO Pwr
ESysResetX
RFC
FBUSTx
Issue 1 06/00