Search for the repair manual for your exact model (not the user manual or installation manual, but the manual that the repair people use). Even if the unit looks lifeless there may be a special sequence of button pushes that can put it into a diagnostic mode.
If that fails I would very carefully use a voltmeter to check power, starting at the outlet (had a friend who very nearly replaced a dryer before figuring out that there was a breaker box he didn't know about that had tripped), then checking power to the controller (could be a bad power supply), and so on. But don't to this if you're not comfortable working with electricity and don't blame me if you get yourself electrocuted!