How to Fix+sunbeamelectric blanketstyle+h85kq+flashes FF

SOURCE: only 1 side of my sunbeam H85KQ mattress pad will

If your model has two heat control thermostats, its possible that there is a fault with one of the thermostats.
Worse would be that the electric cable that runs thru the blanket is broken.
You would need specialised test equipment to find where the break is, unless you can actually feel the cable is split when you run it through your fingers.
Normally, if the electric cable is broken, the blanket is not servicable, because you would have to cut into the cover material to try find the break and replacing the cable is impossible outside of the factory.

SOURCE: One of the controls will not turn on. The cord is

Try swapping the controls and see if the problem stays with the control or the blanket side. In any case I would go on line and contact Sunbeam, they are a very reputable manufacturer and I would be surprised if they do not stand behind the product. You will be able to tell them if it is the control or blanket. If the other side of the blanket gets warm when you switch the controls it is the control if the same side gets warm it is the blanket. If neither side gets warm is is the blanket and control.
Good Luck,
Gilshultz