DIAGNOSIS The on/off rocker switch is the single most common failure point on this model. It's a cheap physical switch that wears out.
FIX Bypass the switch. Unplug the unit. Remove the four screws on the bottom to open the base. You'll see the black rocker switch with two wires (usually red and black) soldered to it. Carefully desolder those two wires and solder them directly together. Reassemble. The coffee maker will now be "always on" when plugged in. Use the wall outlet or a power strip as your on/off switch.
IF THAT DIDN'T WORK The thermal fuse on the heating element may have blown. This is a small white ceramic component near the heating plate. You'd need a multimeter to test it for continuity. If it's blown, you must replace it with an identical thermal fuse (likely 184°C/363°F) to restore power.
HEADS UP After bypassing the switch, the warming plate will get hot as soon as you plug it in. Be mindful not to leave an empty carafe on it for long periods to avoid thermal stress on the glass.