The blower motor requires a solid ground at ground terminal G203 in order to operate.
G203 is located on the passenger side kick panel below the fuse box. it should have either one or three black wires connected to it.
If your original owner's manual is missing, download a soft copy from www.fleet.ford.com
under the MAINTENANCE tab.
1989 Taurus SHO What a project! Retired at 249K.
1997 Ford F150 SC 5.4L - Gone
1995 Mustang GT Convertible, only 68K miles.
1998 Ford Contour Wifey's old daily driver, now mine.
2001 F250 SD, 6.8L, 4 X4.
2007 Mercury Mariner AWD - Wifey's new daily driver