The LEDs on the GPS can indicate different things. Below is a list of what the different flashing sequences mean:
GREEN LED
One slow flash every 3 seconds = looking for GSM network
One short flash every 3 seconds = GSM reception
Two short flashes every 3 seconds = GPRS reception
RED LED
One slow flash every 3 seconds = charging in progress
Solid red light = fully charged
BLUE LED
One slow flash every 3 seconds = looking for GSM signal
Two flashes every 3 seconds = GPRS reception