If my tilt wheel is not in the highest position, the turn signals will not work.
tilt wheel prevents turn signals from working. on 1997 Ford Expedition
I would start by taking the plastic cover off from around your steering column. I have had problems in the past with wire loose in the combination switch harness. pull lightly on the wires were they plug into the switch see if one or more pull out of connector if it dose try to secure it in the harness if not you can but a new terminal end.