Ericsson T18s Trouble-Shooting Instruction page 11

2.4 No SERV at the GSM 900 or the GSM 1800
band.
2.4.1 No SERV at the GSM 900 band.
Measure the voltage drop of the V213 diode (~0.6V, fig. 2.3, class A).
Measure the resistance of R247 (~33 kohms, class A, fig. 2.3).
Measure the voltage at pin 3 of G201 (fig. 2.3) when you're starting the phone.
There should be a voltage peak of ~3.5V.
• If there is no voltage peak, replace V211 (class B), V212 (class B) and C271
(class A, all in fig. 2.3).
2.4.2 No SERV at the GSM 1800 band.
Measure the voltage at pin 3 of G200 when you're starting the phone. There should
be a voltage peak of ~3.5V.
• If there is no voltage peak, replace V211 (class B) and C270 (class A, both in fig.
2.3).
If the fault remains, send the phone to Advanced electrical repairs.
4/00021-2/FEA 209 544/12.B
T18s, T18sc Standard Electrical Repairs
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