User Guide

PAMS Technical Documentation 10. Troubleshooting
NSD-5
Issue 1 05/02 Nokia Corporation Page 13
Power up sequence test:
CCONT digital parts keep MAD4 in reset by keeping PURX down for a delay of 62ms.
Here is the start-up sequence picture:
Ch1 = PWRONX
Ch2 = SLEEPCLK
Ch3 = PURX
Ch4 = RESETX
Phone is Totally Dead
The phone doesn’t take current at all when the power switch is pressed or when the
watchdog disable pin (TPD331) is grounded.
Make sure that the battery voltage you use is within specification (i.e., 3.2 - 4.2V). If the
voltage is lower than that, CCONT hardware (N302) prevents power on.
If the battery voltage is within the specification, change the CCONT (N302).
High current: This indicates that the problem is likely the result of a shorted component.
Check the orientation of major components (including RF) and check for shorts. Likely
components are those that are powered directly from Vbat such as CCONT, the PAs, and
various capacitors.
Low current: This indicates that CCONT is now powering on. Verify CCONT circuitry.
Phone Won’t Power Up
Do a visual inspection. Verify that all parts are on the board correctly, and that none is
missing. Phone won’t power up often is related to VCTCXO solder joints cracking and no
19.2MHz to the BB.