What makes wrinkle cycle to stop working?
If there is a on off switch for the wrinkle release cycle then the switch may be bad or would more than likely be in the timer.
Kenmore dryer, on timed dry the timer does not advance to shut off. Does this need a new timed dry control board?
You will want to check to see if the unit is advancing in all other settings. While it is likely that the control board can cause the unit to not advance during timed dry, it would also cause the same issue in the other cycles as well. If the control board is needed then it would be part number 8558178.