U8950 Maintenance Guide V1.0
10 Principles and Failure Analysis
2012-10-22
Huawei Proprietary and Confidential
69
No-transmission failure troubleshooting process for IMT/PCS/CELL is shown in the
following.
Ensure that the SIM card and the antenna are well connected. Then, troubleshoot the fault
according to the following procedure.
IMT/ PCS/CELL
transmission failure
Check whether J3201
pin 1 and pin 2 are
connected.
Do not
connect the
RF cable.
Check J3201.
Check whether U3201
control signals are
normal.
Check U201.
End
Check whether the
maximum CELL PA
output is about 28 dBm.
Check U3201
and U201.
Check U3302.
Y
N
Y
Y
Y
N
N
Check whether U3801
pins 50, 51, 52, and 53
output IQ signals.
Check U3801.
N
Y
In W900, just replace the U3302 detection with U3402 detection.
In W900, just replace the U3302 detection with U3401 detection.
