案例题目: H55E3A反复重启
关联产品: H55E3A
机芯方案: MSD6A648WY-8-00B2
故障现象: 开机反复重启
故障原因分析: 开机反复重启,用U盘升级升级到40%的时候机器还是重启
检修过程: 机器反复重启,首先升级软件,再检查硬件问题,用U盘升级升级到40%的时候机器还是重启。排除主程序故障测量N30 5VS电源管理芯片输出电压只有3.9V而且波动,测量取样电阻R253、R355、R231未见异常,准备测量C106电容(局部电路如图所示)时,发现有一个脚虚焊,补焊后故障排除!
U盘升级主程序的打印信息如下(删掉了一部分打印信息,因为检修过程文字受限):在实际维修中也可以进行辅助判断!
–35 %
>> mmc write.p 0x20200000 tvdatabase 0x800000 1
–35 %
>> filepartload 0x20200000 $(UpgradeImage) 0x804000 0x13800
–36 %
>> mmc write.boot 1 0x20200000 0 0x13800
–37 %
156 blocks written: OK
>> filepartload 0x20200000 $(UpgradeImage) 0x818000 0x19ac00
–37 %
>> mmc write.p 0x20200000 MBOOT 0x19AC00
–38 %
3286 blocks written: OK
>> filepartload 0x20200000 $(UpgradeImage) 0x9b3000 0x1675790
–38 %
>> mmc erase.p misc
–39 %
MMC erase: dev # 0, user area part, block # 14336, count 1024 (unit: sector)…
1024 blocks erase: OK
>> mmc erase.p recovery
–39 %
MMC erase: dev # 0, user area part, block # 64512, count 163840 (unit: sector)…
163840 blocks erase: OK
>> mmc write.p 0x20200000 recovery 0x1675790 1
–40 %
UART_115200
AC_ON
MIU0_DQS-OK
BIST0-OK
BIST1-OK
#_m
故障板号: RSAG7.820.8281
故障元件: C106