My coffeemaker will not brew. makes buzzing noise and beeps when I turn it on

Your coffeemaker features a Ready Tone that beeps 5 times when coffee is finished brewing. To turn this alert off, press Tone button; an icon will appear in display to indicate tone is off. To turn tone back on, press Tone button again; icon will disappear.

I see two problems that you've described.

First, you have a bad empty-reservoir sensor. Mine went out on my first Mr. Coffee within the first month also. The purpose of the sensor is to trigger the beeping to simply let you know when the coffee is done. The coffeemaker would normally work fine otherwise.

Second, you have a bad heating element. This is the core function of your coffeemaker and renders it useless for anything but a nice warming plate.

I recommend replacing the coffeemaker.

In the future, make sure you do not add water to the reservoir unless the coffeemaker has been turned of for at least five minutes. This will help prolong the life of the heating element.

The heating element will naturally degrade over time. But, it can incur sudden damage when the reservoir is refilled with water too soon - while the element is still hot. Because of the simple design, if the coffeemaker is on, then both the warming plate's heating element and the reservoir's heating element are on. So, after a brewing cycle is complete, the reservoir's heating element stays on. Without any in the reservoir to keep it cool, the heating element superheats. So, if water is put in the reservoir while the coffeemaker is on or before the element has adequately cooled, the sudden burst of steam from the water contacting the element can be quite violent.

There is no self clean button on mine, and I have done the above with vinegar and water......what next?

Decalcification
Decalcification refers to the removal of calcium
deposits which form over time on the metal
parts of the coffeemaker.
For best performance from your Brew Central
Thermal™ Coffeemaker, decalcify the base unit
from time to time. The frequency depends upon
the hardness of your tap water and how often
you use the coffeemaker. The flashing Clean
light will indicate when you should clean your
coffeemaker.
If the Clean light begins to flash when the
coffeemaker is turned on, it is telling you that
the calcium buildup is interfering with the
functioning of your coffeemaker and the flavor
of your coffee. To clean, fill the water reservoir to
capacity with a mixture of ¹⁄³ white vinegar and
²⁄³ water. Press the Clean button. When the self
clean light glows, turn the coffeemaker on by
pressing the on/off button. The Clean light will
shine steadily. The coffeemaker is now in Clean
mode. One cycle should be sufficient to
adequately clean the coffeemaker. When the
cycle is completed and the five beeps sound,
the coffeemaker will shut off. Turn the
coffeemaker ON to see if the Clean light
continues to flash. If it does, turn it to OFF and
then repeat the cleaning procedure with a fresh
solution of vinegar and water.
If the Clean light no longer flashes, turn the
coffeemaker to OFF and then run one cycle of
fresh cold water through the unit before using
the unit again to brew coffee.
Notes on the Clean F unction
Pressing the Clean button cancels all other
settings. If it is pressed accidentally, press it
again to return the coffeemaker to all its
previous settings. Pressing ON/OFF will also exit
the Clean Mode and turn the coffeemaker OFF.
Directly from the DCC-2400STR manual

The CBC-1600 is designed differently than you might expect. The stainless steel, insulated carafe is designed to keep the coffee hot instead of a hot plate keeping a glass carafe hot. Some people like that style better (including me). Some people - like my dad - don't think it keeps the coffee hot enough.

Your coffee maker is working exactly as designed. The carafe itself is designed to keep the coffee at the same temperature as it was brewed.

on my 12 cup kitchenaid coffee maker, i can press and hold the Auto button to enable/disable the alarm

A common problem that can occur with the Cuisinart coffee maker is it will stop brewing, even when there is water ready to be transformed into coffee. The machine still turns on and works like it should, but does not continue brewing an entire pot of coffee, and acts like it has finished brewing even when there is still water sitting in the bin. This type of problem is pretty common among various coffee makers, and usually occurs when there is a problem inside the machine.
One of the best ways to fix this problem is by flushing the coffee maker out with a vinegar solution, which can be made with equal parts of vinegar and water. It should be poured in the same place as the water that is ready to be brewed, and will help to clear out the machine and make it ready to start brewing again. This problem is usually caused by calcium building up within the machine, and the vinegar helps to clear out any blockage to help it start running smoothly again.

Try cleaning it with pure vinegar. 3-4 times just keep running it through the machine.

You can try vinegar/water cleaning, but this may be mechanical/electrical.

According to the manual for IS series Mr. Coffee for programmable models:
1. Prepare one batch of Mr. Coffee coffeemaker cleaner. Pour the mixture into the water reservoir. Remove the water filtration disk from the machine.
4 cups or 20 oz. of undiluted, white household vinegar may be used as a substitute for the cleaner.
2. Place an empty paper filter or permanent filter into the filter basket and close.
3. Place the empty decanter back in the unit, centered on the warmer plate.
4. Press SELECT button until the red CLEAN indicator light is illuminated. For your convenience the cleaning cycle is automatic. The entire cycle will take 45-60 min to complete. During the cleaning your coffeemaker will:

• Slow brew approx. 3 cups of cleaning solution.
• Pause for 30 min (the CLEAN light will remain on to alert you that the process is active). At the end of the pause period your coffeemaker will beep.
• After 30 mins your coffeemaker will brew the remainder of the cleaning solution.
• When complete, the CLEAN light will turn off and your coffeemaker will automatically beep and shut off.

5.Discard the cleaning solution and rinse the decanter thoroughly with clean water.
6. Fill the water reservoir with clean fresh water.
7. Place the empty decanter back on the coffeemaker, centered on the warmer plate.
8. Remove and discard the filter used during the cleaning cycle and replace it with a fresh paper filter. If a permanent filter was used during cleaning, remove it and rinse it thoroughly before replacing it in the filter basket.
9.Begin brewing and allow the full brew cycle to complete.
Repeat steps 6-9 one more time.