RH-128
Baseband Description and Troubleshooting
COMPANY CONFIDENTIAL
Copyright © 2009 Nokia. All rights reserved.
Issue 1
Page 5-14
1. Check if the following voltages of PMU are normal: VBAT, VDD_DIG, VDD_CORE,
VDD_TXPLL, VDD_TCXO, VDD_RX, VDD_TX
2. If the voltages are abnormal, check the fault reason.
Case Two:
1. If current is zero, check CN801 and C509, C510, C512, C513, C514, C515. If there is no
power output, PMU is defective. Phone cannot be repaired and must be replaced.
Case Three:
1. Raise the voltage of PS-HOLD, and measure every output voltage of PMU, (the reference
clock Power-on needed is 19.2MHZ).
such as :VDD_DIG,VDD_CORE,VDD_TXPLL,VDD_TCXO,VDD_RX,VDD_TX ;
2. Check if the clock TCXO
（
19.2MHz
）
and RTC
（
32.768KHz
）
are normal.
3. If the signals are abnormal, please check the fault reason.
4. If it is normal, please check the welding of the CPU and Flash and perform welding or
replacement. (Replacement includes Flash Updating). The welding of the display panel
connector should also be checked, because the shortcut of the parallel data signal and Read &
Write signal on the display panel connector will lead to failure of CPU in invoking the programs
of FLASH.
Power Does Not Stay ON Troubleshooting
