just an idea and prob a stupid answer but ive got an 08 nitro auto/5spd and my check tranny light kept flashing... being its new i took it to the dealer they plugs it up pulled a code and all it was, was low fluid... witch was my first thoughts but again being new and warrantied i didnt touch it... also another thing the guy there said is that it may have been a bubble/air pocket in the coolant line and the sensor is being thrown off as to where there may not be fluid flowing threw... good luck...