Armature Grounded Circuit Test
WARNING: This page is about a different car, the 1997 Mercury Mountaineer and 1997 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
Using an ohmmeter, check for continuity between any commutator segment and armature laminations. See Fig 1 . If ohmmeter indicates less than infinite resistance, armature is shorted and must be replaced.