DIAGNOSIS The machine is powered but the brew cycle isn't initiating. This almost always means the thermal fuse has tripped because the water reservoir was empty or very low when you last tried to brew.
FIX Unplug the machine and let it sit for at least 30-45 minutes to cool down completely. The thermal fuse is a safety device and needs to reset. After waiting, fill the reservoir with cold water all the way to the 12-cup line, plug it back in, and press the brew button. It should kick on.
IF THAT DIDN'T WORK The internal thermal fuse might have failed permanently, which is a known failure point on this model. You'll need to replace the thermal fuse or the whole heating element assembly, which isn't a casual DIY fix.
HEADS UP Always make sure there's water in the reservoir before you turn it on. Running it dry is the main thing that trips this fuse.