Nokia RH-41 Series Troubleshooting Instructions page 8

RH-41
Troubleshooting Instructions
1 Power key pressed
• After 20ms UEM enters RESET MODE if VBAT>Vmstr+
• VFLASH1, Vana, Vcore, Vio and VR3 goes high.
• VCTCXO enabled by VR3 -> RFClk 19.44 MHz running.
2 Purx released
• Purx released by UEM, UEMINT goes high for 100 ms, SleepX goes high and
UEM starts feeding SleepClk (32 KHz) to UPP.
Note: The sleepclock starts running in the crystal circuitry (B200) immediately when the battery volt-
age is supplied.
3 Software running
• Default value for Vcore is 1.5 volts when the software is running.
• Cbus (1.08MHz) clock starts running.
Phone does not start up normally or does not stay on
Note: In case of power up faults, it is not possible to force the phone on by disabling the watchdog.
Instead, measurements should be taken immediately when the power key is pressed or when the bat-
tery voltage is connected to the phone (local/test mode).
The easiest way to check if the software is running when the phone takes an abnormal
amount of current is to measure the cbusclk and Vcore.
The Dbus clock (programmable 9.72MHz) is not automatically visible in the test and local
modes.
Page 8
Nokia Corporation
CCS Technical Documentation
Confidential Issue 2 09/2003