lights flashing on 1995 Mazda B3000

my 4x4 lights are flashing,after changing alternator yesterday . i checked all my fuses wont engage into 4 wheel drive

Asked by for the 1995 Mazda B3000
The flashing light is indicating that the computer has detected a fault in the 4WD system. Get it checked by a Mazda or Ford specialist or a 4WD shop.
If you want to find a specialist, here's a directory link for you: