Latitude 6500 status lights

Latitude E6500. I closed the lid and when I opened it a few hour later, these three "status lights" were BLUE and the system would not turn on. The status lights are just above the keyboard. Each is a suitcase or a lock with a symbol in it. The first has the number "9", the second an "A" and the third, a downward pointing arrow. Please can anyone tell what this means and how I can restart the laptop. I already removed the battery and reinserted it. No change