Automatic car? There's a curved shaped switch, on the column, under the dash, called the neutral safety switch. On it there is a connector with a pink wire and a green wire. This part of the NSS is for the reverse lights. Guessing the green has power on it all the time and should only have power on it when the shifter is in "R".
Then there should be another harness plugged into the connector I mentioned if someone wrapped it under the car. May have been rod driven and someone removed the rods. Check around on top of the column for that connector.
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