[RSchuetze]

Lower heating element no longer heats, appears to be cracked and bubbled up like something was baked on it, but the stuff bubbled up does not appear to be food, but more like metal that has melted. Is this likely? Also control panel is going dim for the 3rd time. What do you suggest?

[denman]

Here are your parts
Replacement parts for SMW272YB models | AppliancePartsPros.com

Lower heating element no longer heats, appears to be cracked and bubbled up like something was baked on it, but the stuff bubbled up does not appear to be food, but more like metal that has melted. Is this likely?
Yes the element has to be replaced, it had a hot spot and the internal heating wire has broken.
To double check it remove it and check it with a meter usually around 10 to 20 ohms.

Also control panel is going dim for the 3rd time. What do you suggest?
You will have to replace the control again.
I cannot say that the following applies to this unit but it is common on other units especially JennAire.
On the board there are a number of electrolytic capacitors, one or more of them are in the displays power supply. Over time they loose the ability to hold a charge and the display dims till it is unreadable. You could try replacing these capacitors. Unfortunately I do not know which one is for the display so I would replace all off them. This has about an 80% chance of fixing the board.

[denman]

Also here is a good thread about dim displays
Thermador display is very dim