What do the LED lights on the iTRAC2 wheelhouse unit indicate?

If you have an iTRAC1 the green LED light indicates power, and this should always be steady, as it being off means there is a power issue. The amber GPS LED and red Satellite LED will intermittently turn on when a position is being logged and transmitted. The iTRAC2 has an additional LED for indicating a message is waiting to be retrieved and once the iMailer software has read it, the message LED will turn off.