A/C Blower not blowing at high speed on 1996 Ford Windstar

all of a sudden my a/c blower does not run at high speed when a/c max is selected. It runs at very slow speed no matter which fan sped is selected. Does it need replacing or is something else wrong which is fixable?

Asked by for the 1996 Ford Windstar
Could be the heater blower resistor failing. Or you could have a weak blower motor.
where is this resistor located and how difficult is it to replace the motor or resistor
The resistor is located behind the glove box attached to the evaporator housing (the plastic box that holds the evaporator core and heater core). Not hard to replace - two screws and a wiring connector. The blower motor is in the same area.