On my 2016 Sentra O/D and light came on and went into low gear by itself wiWhy did this happen? It revered up to 3500 rpm's and stayed ther.
a sensor or something internal to the trans is faulty. Have a shop diagnose the issue. since the light is on, there is a code or codes stored helping them to determine the problem.
Your warranty should cover any problems. Take it to your Nissan dealer.
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