If you own a no-name or cheap Chinese GPS tracking unit please read following information.
Different Chinese manufacturers and sellers brand their devices under similar popular names (e.g. TK102, TK103, GT02A, H02 and other), so it’s impossible to identify correct port for those devices just by a model name. If you have one of those devices please try all following ports:
There are two additional common issues:
Device sends status information, but not GPS coordinates. Most often it this happens with devices that use GPS103 protocol (port 5001). The solution is to send a command to the device to activate location reporting: fix060s**n123456 (where 060s is the interval between messages, ** tells the device to continue sending locations periodically and 123456 is the default password). TrackMe does not support commands yet, so you need to send SMS command from your phone.
Devices that use TK103 protocol (port 5002) use 12-digit device identifier instead of IMEI. Usually it consists of 11 last digits from IMEI plus leading zero. For example, if IMEI number is 123456789012345, the unique id would be 056789012345.