Keurig B77 Troubleshooting
If your coffee is not brewing as hot as it should be, then your heating mechanism has probably shut off. This is due to your water pump functioning incorrectly. When water is not being pumped through the brewer, the heating device shuts off to prevent the coffeemaker from overheating. Similarly, if the water pump is working but not at max efficiency, the coffeemaker signals the heating device to shut off. You will have to reseat your water reservoir.
The Keurig B77 could be making a higher pitched noise because the pump has to force water through a smaller opening to deliver the water to the K-Cup. This is due to a build-up of scale in the tubing. You will need to clean out your device with white vinegar.
When you try to make a cup of coffee right after another cup, the 2nd cup is not made fully or does not get made at all. This generally occurs when the magnet holding the water reservoir in place vibrates out of its original spot. To fix this, you will have to realign the magnet holding the water reservoir in place.
If your machine has difficulty brewing the entire cup or fills it with mostly water, then it is probable that your pump is being clogged with scale, which obstructs the flow of the liquid in the device. You will need to clean out your device with white vinegar.