Soot on bottom of dishwasher - Maytag 24 in. MDB5600A Jetclean II Built-in Dishwasher

Surly there is no 'soot' in your dishwasher unless you have had a fire in it. It is more than likely mold if you haven't used it for a while and it can be removed by wiping it out with a chlorine solution.

The "soot" is probably pieces of melted rubber from your belt. Replace it at least twice per year.

check gas pressure if too low it soots up and overheats

If you are cooking with propane or natural gas, you may need a new regulator for your range, the black soot is most likely too much gas being used to make the flame. But, as for the soot on the bottom of your pans, try letting the pan soak in a mixture of baking soda and water, then attack it with a brillo pad. Hope this helps!

Yes the burner needs cleaning . Yellow is lack of air causing soot and co2 . turn off do not use . needs a service and to find out why its sooting

You don't have the right Gas to Air ratio..... Not enough air to the burners or you are running to low of gas pressure for propane... Propane takes a smaller orfice or operate than Natural Gas.....
You should have 10" of WC for Propane operation..
You will need a manometer to check it.
The flame should be a blue color with no yellow in it. There should be air shutters right at the orfice to each burners. You will have to play with the adjustment to get the best blue flame with no yellow in the flame.... Hope this helps.....

Is it tripping the breaker in the breaker box? If so you have a short to ground. Could be A bad spot on the dishwasher cord. Turn power off and pull dishwasher out and check the power cord all the way back to the dishwasher terminals

Has to do with the detergent you are using is not completely breaking down the food materials being removed from the dishes during washing. I ran the dishwasher empty through a pot and pans cycle with maximum options and some bleach, Cleaned it to like new condition and from now on I use a detergent that has bleach in it. Cascade has several different products to cover this.

Wellif you uninstalled and reinstalled the same appliance it should work the same.. thats weird that it changed. however the black soot is usually from flames that are to high. you could try tightening down the orifice where the gas comes out.

You can get a product called dishwasher majic. It is used to clean the tub of a dishwasher. Big box stores (LOWES, HOME DEPOT) should have it. There is not charcoal in the unit. I suspect is grease from the rubber seal around sump assembly.