There are two possibilities:
- No power to the panel
- Control panel is defective
At the panel, there should be a wire cable running from the panel to a tan (usually) or grey (rarely) power cube. This is the power transformer. Check to make sure that it is plugged in.
You mentioned that you had to disconnect wires to get it to stop making noise... I suspect that those wires were the power wires from the transformer... If so, you will need to reconnect the wires to terminals 1 and 2 on the panel. You should find and unplug the transformer first, as shorting the board can fry it.
To eliminate the siren noise from the panel sirens, disconnect the wire from terminal 3.
