It will reset itself if there is not a fault continually turning it on. I would go to the nearest Autozone and have them connect a scanner and read and reset the codes. It's free. Second choice is to disconnect the battery for at least 30 seconds. If you do that the tranny computer has to relearn your driving habits. This can take several days. You may experience hard shifting. If the light comes on again come on back.
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96 Gr Caravan LE 3.8, 212K miles
07 Fusion / 06 RAV 4 / 06 Accord