All 3 lights on indicates a fault. Now this could be anything so best thing to do is check the fault code.
To do this go to the diagnostic port under steering column and identify pins 1 and 4. Link a short bit of wire or paperclip into these pins. Then turn on the ignition without starting the car and count the flashes from the Ayc lights. Then get back to us.
Long flashes are tens short flashes are units. Ie 3 long slow flashes and 5 short fast ones would be code 35
