Problems with Huawei UMTS Modems:

Bus 001 Device 005: ID 12d1:1446 Huawei Technologies Co., Ltd. E1552/E1800/E173 (HSPA modem)

vs

Bus 001 Device 005: ID 12d1:1436 Huawei Technologies Co., Ltd. E173 3G Modem (modem-mode)

Solution

pi:/root # cat /etc/udev/rules.d/41-usb_modeswitch.rules 
ACTION=="add", SUBSYSTEM=="usb", ATTRS{idVendor}=="12d1", ATTRS{idProduct}=="1446", RUN+="/usr/sbin/usb_modeswitch -v 12d1 -p 1446 -I -M '55534243123456780000000000000011062000000100000000000000000000'"