故障现象 诺基亚3210型手机屏幕显示不入网,手动也收不到网络。 分析检修 当手机不能入网时,应检测射频供电管V101(P28)4脚电压,如果有3.3V左右的供电输出时,一般为音频处理模块N200部分脚有虚焊或脱焊故障,这时只需重新焊接即可。N200既是音频处理器,又是数据双向调节器,由于N200为BGA封装形式(内置焊脚), Symptom Nokia 3210-type mobile phone screen does not show network, manual also can not receive the network. Analysis and maintenance When the phone can not access the network, should test the RF power supply V101 (P28) 4-pin voltage, if there is about 3.3V power supply output, the audio processing module N200 is generally part of the foot Weld or weld off the fault, then only Need to re-welding can be. N200 is both an audio processor and a data bidirectional regulator. Since the N200 is a BGA package with built-in solder fillets,