FORD 2014 E-450 v.3 - Manual (Page 267)

When your temporary spare tire is installed
When one of your road tires needs to be replaced with the temporary
spare, the tire pressure monitoring system will continue to identify an
issue to remind you that the damaged road wheel or tire needs to be
repaired and put back on your vehicle.
To restore the full function of the tire pressure monitoring system, have
the damaged road wheel and tire assembly repaired and remounted on
your vehicle. For additional information, see Changing Tires with a
Tire Pressure Monitoring System in this section.
When you believe your system is not operating properly
The main function of the tire pressure monitoring system is to warn you
when your tires need air. It can also warn you in the event the system is
no longer capable of functioning as intended. See the following chart for
information concerning your tire pressure monitoring system:
266 Wheels and Tires
2014 Econoline (eco)
Owners Guide gf, 3rd Printing, September 2013
USA (fus)