Gear Selection is NOT totally Electronic.
If you put it in 1, and it doesn't shift into 1, you may have had the Transaxle pump blow its gasket.
Shifting into 1 or 2 has a MANUAL counterpart that overrides the electronics.
Are you getting a flashing O/D light or a Check Engine light ?
Put it in gear, and let it sit for a few minutes, and see if the lights come on.
The poorest parts of our transaxle (CD4E) are the Valve Body, and the Pump.
The Valve Body is easily replaceable, because it doesn't contain any check balls.
The Pump requires disassembly of the transaxle.
Both require removal of the transaxle, which is a minimum of $500 labor.
The Valve Body does wear out prematurely, and the early CD4E Transaxles are known for blowing the Pump Gasket.
All of this info can be found at...
TransOnline I showed this site to my Service Manger, and he can't believe
the amount of information that is here that even he WASN'T aware of.
He even wishes that FORD would post some of this stuff !
Replacing the Transmission Range (TR) Sensor on the transaxle,
will guarantee that you have all of your electronics in working order.
Also check the Harness Connector on top of the Transaxle, to the rear of the TR Sensor,
(You can see it if you remove the Air Filter box.)
and the harness to the Solenoids, which should be on the transaxle, right below your battery.
After you've done all of this, if it still doesn't respond,
depending on your mileage. you might need the solenoids and/or valve body,
or a total rebuild.
If you opt for the total rebuild, then get yourself a shift kit,
so your rebuild lasts that much longer !