To troubleshoot a Mr. Coffee coffeemaker, use lemon wedges and salt to clean the decanter, immerse the machine's plastic components in soapy water, and pour distilled white vinegar onto the reservoir. Prepare a soft sponge, filtered water, kitchen thermometer, ground coffee and coffee filter.
Put the lemon wedges in the decanter after squeezing them, and sprinkle some coarse salt on the lemons. Shake the decanter to clean its interior thoroughly. Repeat the cleaning method as necessary, and wash the decanter with hot water afterward.
Disassemble the Mr. Coffee machine before soaking the plastic parts in soapy water. Use a soft sponge to wipe the components. Next, reassemble the coffeemaker, and fill half of the reservoir with distilled white vinegar to clean it. Plug the machine into an outlet, and start a brew cycle. Repeat the cleaning procedure after the cycle is completed.
Pour filtered water into the machine until it reaches the fill line, and perform a brew cycle to get rid of the vinegar. Add sufficient ground coffee, then run a brew cycle with filtered water filling half of the reservoir. There should be no leaks or clogs throughout the cycle.
Once the brew cycle is finished, dip a thermometer into the decanter. The appropriate temperature ranges from 185 to 205 degrees Fahrenheit. Repeat the cleaning process if brewing or temperature problems are not resolved.