Just like the good Dr. above, I too have a degree in engineering from the Cow College.
You have some sort of motor controller board.
The black and white wires to the left are the AC input.
The big red disk is a MOV sort of a protection against voltage spikes.
S1, S2, and S3 are the control signals fromsomewhere else.
Of the devices on the heat sink, two are SCR's (Silicon controlled rectifiers) and the middle three are just big diodes.
Evidently, the diode in the center got HOT!!!! Probably caused by its motor drawing way too much current (jammed?).
Before soldering a jumper wire, check the diode with a Volt / Ohm meter. Most nowadays have a diode checking position. Touch the VOM leads to each leg of the diode then reverse your VOM leads. In one position the diode will show a lower resistance and in the other, a very high resistance. If you see a high resistance in both directions, you have a blown diode. Not hard to replace.
If you do have a good diode, figure out WHY the motor is not feeling well.
A other have said - solder a jumper wire across the burnt leads and Stand Back! What have you got to loose.