Turn lights wont work - 1994 Ford Econoline

The indicators have a few components in their system, being: The indicator switch The Flasher Unit/Relay The fuse & wiring The bulbs The Hazard light switch.
If the hazard switch is broken or disconnected it will stop the indicators from working, so you could check that. You can check the indicator fuse, which should be labeled on the fuse cover. If it is blown, there is likely a fault that has caused it to blow, more often than not a problem with the trailer hitch or a trailer that has been towed. The next culprit is the flasher unit. They are usually found in the fuse area, it is a black box, looks much like a relay, but slightly taller. If this is faulty it will cause the indicators to either stay on without flashing, or not work at all. You can check this by disconnecting it, and connecting a test light to the terminals, one at a time while working the indicator stalk (key on) If the light lights up then this confirms the switch is okay, and the flasher is likely faulty.