not "ALL" ev100s have codes or a way to display codes, only ev100 systems that were LX and later have a way to display a code. if your ev100 card has a window with trim pots then you may not have any codes.
In any case the next step is to read voltages on the 6 screw term strip during the start up sequences and confirm the proper operation of the switches at the proper times. If the input is in the wrong order, or some circuit is closed when it should be open, the safety 'static return to off' circuitry will prevent normal start-up.