Gps Module - Nokia 6255 Description And Troubleshooting

6255/6255i6256/6256i (RM-19)
Baseband Description and Troubleshooting

GPS Module

The GPS circuitry utilizes RF signals from satellites stationed in geosynchronous orbit to
determine longitude and latitude of the handset. The GPS circuitry is completely separate
of the CE circuitry and is located almost exclusively on the secondary side of the PWB
underneath the display module.
Use the following steps for basic GPS BB troubleshooting:
1. Always perform a visual inspection on the GPS circuitry to see if the problem is
physical (dislodged parts, corrosion, poor solder joints, etc.) before performing a
diagnostic test.
2. Put the GE and CE in the proper mode
3. Check to make sure that necessary inputs from the CE are good (power, clock,
etc.).
4. Ensure that these inputs produce the proper outputs.
Because of the large level of integration (most functionality is contained in the two ASIC
chips), the amount of diagnostics one is able to do is limited.
Page 48
Figure 35: GPS Block Diagram
©2005 Nokia Corporation
Nokia Customer Care
Company Confidential Issue 2 05/2005