已发送AT%IPOPEN指令后GPRS就自动关机

我用的是GTM900-B模块，发送的指令如下：
AT+COPS?
+COPS: 0,0,"CHN-CUGSM"
OK
AT+CSQ
+CSQ: 11,99
OK
AT%IOMODE=1,1,0
OK
AT+CGDCONT=1,"IP","CMNET"
OK
AT+CGDCONT?
+CGDCONT: 1,"IP","CMNET","",0,0
OK
AT+CGREG?
+CGREG: 0,1
OK
AT%ETCPIP="user","gprs"
OK
AT%ETCPIP?
%ETCPIP:1,"10.225.1.59",,"120.80.80.80","221.5.88.88"
OK
AT%IPOPEN="TCP","192.168.1.103",666
每次一发AT%IPOPEN="TCP","192.168.1.103",666之后，板上的signal指示灯就急闪几下关机了
我用的是联通卡，用花生壳建的端口映射，因为用了路由器，IP填的是本机显示的，网上查到的IP是183.233.189.9这个
求救啊！！@发烧友