Gps - Nokia 6255 Description And Troubleshooting

Nokia Customer Care

GPS

GPS faults
Is VCORE at 1.5V?
YES
Is VIO at 1.8V?
YES
GPS_RF_CLK
(19.2MHz) OK?
YES
GPS_EN_RESET held
high?
YES
GPS_SLEEPCLK
(32.768KHz) OK?
YES
VRF_GPS OK?
YES
GPS_CLK (16.368MHz)
OK?
YES
Test Mode 1 OK?
YES
CE sending code
download signals?
YES
SPI interface active?
YES
RF data and clock?
YES
Debug RF front end
Issue 2 05/2005
Troubleshoot CE
NO
power supply
NO
Troubleshoot CE
NO
VCTCXO circuit
If the BB ASIC is being
held in reset,
NO
troubleshoot the
source in the CE
Troubleshoot CE sleep
NO
clock circuit
VRF_GPS regulator
NO
enable line low?
YES
Replace TCXO or GPS
NO
NO
Replace GPS BB ASIC
Determine why CE not
NO
sending download
NO
Replace GPS BB ASIC
NO
Replace GPS RF ASIC
©2005 Nokia Corporation
6255/6255i6256/6256i (RM-19)
Baseband Description and Troubleshooting
NO
RF ASIC
signals
Company Confidential
Replace regulator
N052
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