Ericsson I 888 Trouble-Shooting Instruction page 8

I888, Standard Electrical Repairs
2.2 Connect a call.
To test GSM900,connect a call at power level 5 against the instrument with the input
signal at -68.5 dBm. To test GSM1900 use power level 0 and an input signal at -68.5
dBm.
If it works, proceed to section 2.3. If it doesn´t work, then it probably is a TX related
fault. If it is only at channel 1 (or several of the lower channels) you can´t connect a
call, is it N570 (class D, Fig 2.2) that is faulty and the phone can´t be repaired at this
level. Open the phone and check for liquid damages. Make sure the antenna connec-
tion X101 (class A, Fig 2.1) isn´t mecanically damaged, unsoldered or dirty (var-
nish, glue, oxide...).
Measure the resstance between test point P401 (Fig 2.3) and ground (or between
N401:14 (Fig 2.2) and ground). The resistance should be larger than 5 kOhm. If it is
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