Phone Register Failure - Nokia NSE–6 Series Disassembly & Troubleshooting Instructions

PAMS
Technical Documentation

Phone register failure

Phone doesn't register to network or
phone doesn't make a call
Analog supply voltage VCOBBA is > 2.7 V
at C280 (C281, C282..)
Analog reference voltage Vref is 1.5 V
at C251 (R253 lower side)
– During the receiving slot:
Supply voltage VCP (J220) > 4.8 V
Supply voltage VRX (C148, C543..) > 2.7 V
Supply voltage VSYN_1 (C144, C505..) > 2.7 V
Supply voltage VSYN_2 (C143, C641..) > 2.7 V
– During the transmitting slot:
Supply voltage VTX (C145, C746..) > 2.7 V
Synthesizer lines:
SEna: Summa N540 pin 7
SClk: Summa N540 pin 5
SData: Summa N540 pin 6
pulses 0 ––> 1 during receiving slot
RF control lines:
RxC (R263 upper side) 0 ––> 2.3 Vmax
AFC (R660 upper side) 0 –– 1.2 Vtyp
during receiving slot
Analog data signals RxIP and RxIN (R544 upper sides)
0 ––> 1.5 V DC during receiving slot
Used benefit signal is biased to DC and its amplitude
is 50 mVpp nominal and frequency is 13 MHz
RF control lines:
TxC (R740 upper side) 0 ––> 2.3 Vmax
TxP (Summa N540 pin 32) 0 –– 2.8 V
during transmitting slot
Analog data signals TxIN, TxIP, TxQN, TxQP
(R749, R748, R746, R745 upper sides respectively)
0 ––> 0.8 V DC during transmitting slot
Used benefit signal is biased to DC and its amplitude
is 300 mVpp nominal and frequency is 64 kHz
Original 08/98
Disassembly & Troubleshooting Instructions
YES
NO
YES
NO
YES
YES
NO
YES
YES
YES
YES
Check CCONT (N100)
Check R253, R251
NO
Check CCONT, MAD2
(N100, D200)
Check MAD2 (D200)
NO
Check COBBA (N250)
NO
Check COBBA (N250) if DC failed
Check RF if benefit signal failed
NO
Check COBBA (N250) if TxC failed
Check RF if benefit signal failed
NO
Check COBBA (N250)
YES
Check RF
NSE–6
Page 17