why causes a transmission to go into failsafe mode? on 2001 Nissan Sentra

My car is apparently only running on third gear and does not seem to shift to other gears.

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1 answer
ITS 2ND GERA AND YOU MUST HAVE TRANS CODES TO MAKE IT DEFAULT TO FAIL SAFE. GET A FREE DIAG AND EST FROM AAMCO THEN CK PRICES