• Is the unit plugged in? .......Duh
• If yes, check the power cord, obviously, and the plug, there seems to be a very high incident of power cord failure around the strain relief.  Also pull the front panel off and check the 8-pin amp connector on the circuit board, usually when the motors are worn they tend to draw more current and cause the hot and neutral amp connections to burn up, check the black and white (hot/neutral) connections to the circuit board and reterminate as needed, you may need to lay down a new trace on the back side of the board to repair it.  also make sure the front and back side of the board are soldered, there are feed off traces on both sides of the board.