机型：L50P2-UD 机芯T968 故障现象：灯亮不开机维修与分析：服务工程师送修主板，通电试机打印信息就是这样： GXTVBB:Fixed PLL lock failed BL1:ee57c+:7a1241;FEAT:EDFD718C;POC:3;RCY:0;EMMC:0;READ:0;CHK:0; no sdio debug board detected TE: 300653 BL2 Built : 16:14:20, Sep 30 2016. gxtvbb gfdb57f2 -xiaobo.gu@droid05 set vcck to 1100 mv set vddee to 1100 mv init panel power Board ID = 1 SYS PLL lock check 1 SYS PLL lock check 2 SYS PLL lock check 3 SYS PLL lock check 4 SYS PLL lock check 5 SYS PLL lock check 6 SYS PLL lock check 7 SYS PLL lock check 8 SYS PLL lock check 9 SYS PLL lock check 10 SYS PLL lock failed! reset…一直重复打印，先检查主板上各个稳压供电，发现 UD018输出处没电压，断电测量发现 UD018输出处对地短路，拆 UD018下来输出处还是对地短路，仔细检查外围电路发现 C031短路，更换后故障排除！
