You probably have a EL display. No, there NOT leds. They take a higher
voltage to make them work. Typically 40 to 100 volts.
If there is a higher voltage at the terminals and its dead, the display is
bad. If not, the power inverter the supplies the display is bad.



I've never seen an EL panel used in a car stereo, might be some that use it,
but most just use small incandescent bulbs, why I have no idea since LED's
have been quite mature and inexpensive for a while now.