$ lsusb
Bus 001 Device 008: ID 12d1:1c0b Huawei Technologies Co., Ltd. E173s 3G broadband stick (modem off)
$ sudo nano /etc/usb_modeswitch.d/12d1:1c0b
########################################################
# Huawei E173s
DefaultVendor= 0x12d1
DefaultProduct= 0x1c0b
TargetVendor= 0x12d1
TargetProduct= 0x1c0b
CheckSuccess=20
MessageEndpoint= 0x0f
MessageContent= "55534243123456780000000000000011062000000100000000000000000000"