since you have power and assuming your motor is ok, it could be the black covered plastic hex cable(from seat motor to gear) has stripped and is turning freely. try pushing on the cable as you activate the switch to see if it will catch.

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1993 Mercedes Benz 300D 2.5 205K (ex wife's)
1984 Mercedes Benz 300SD 320K (SOLD)
2004 Mercedes Benz C240 75K
1995 GMC Sierra 2WD 5.7L 188K
1983 Mercedes Benz 300SD 239K (SOLD)
1987 BMW 325i 220K (SOLD FOR SALVAGE)

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