LED Behavior Indicates Solid amber The AirCard is powering up. Blinking amber The AirCard is searching for a channel. Solid Green A voice call is in progress. Blinking Green The AirCard has acquired a channel and is in idle mode. Solid Red An error has occurred.
You might try and remove and re-install the sim card. You might try another sim card, one from a working phone. (just remember any web browsing uses data rate charges for that sim card) You can also, verify the sim chip works by placing it in your phone, and make sure it links to AT&T (Just dont make any phone calls or it will be 45 cents an min.. ) that will at least verift the chip is good..