Sears Kenmore HE3 Gas dryer, serial # mp4415027.

The dryer is working normally intermittently. When it is not functioning properly, it works only on the delicate setting, and if I try to change any of the settings, it just jumps back to delicate. When I try to turn it off, the led lights which indicate the cycle and the running time remain on. The interior light is not working eat all, although in the past several months, the light has been coming on by itself even when the dryer is not in use and the door is closed.

I called a repairman and he says it needs a new circuit board, which apparently is the whole top portion of the dryer, and the part alone is $350.
A few hours after he left, the dryer began working properly again.
It seems likely that the circuit board may just has a loose connection somewhere, and possibly doesn't need to be replaced.
Please advise me, and save me a $450 repair bill.

Thank you so much.