I have a Maytag electric dryer model # MED5770TQ0 that will not heat. What could be the problem?

First, you can download a manual from here:

http://www.maytag.com/support/manuals_literature.jsp

There is a parts list and a parts diagram. Unfortunately, I don't see a wiring diagram. They're often taped to the inside of the console.
There is a trouble-shooting page. Go through that first. It's the easy stuff (fuse blown).

1. No power to dryer
2. Heater burned out
3. Open thermostat(s)

Those are just some of the possibilities. If you can check some of these and post back, we can probably help you from there. Try these tests first:

1. Disconnect the power. Locate the heating coil. Disconnect wire from one end of the heating coil. Using an ohmmeter, check for continuity. If no continuity, heating coil is bad.

2. Reconnect wire to end of heating coil. Reconnect the power. Dryer needs to be turned on. With voltmeter on 250 VAC scale, carefully check for voltage across heating coil. You may have to clip some leads to the ends of the heating coil so you can measure the voltage with the dryer on. There should be 240 VAC across the heating coil. If voltage is not present, you need to trace the wiring to the device where the voltage disappears. A wiring diagram is valuable for this.