the vehicle is a 1994 volvo 940. it belongs to my mother, and i dont know much about these cars, and the problem description i have is quite vague. basically what she tells me is that as soon as the vehicle start up, when warm, she claims it goes into "shiftlock override". she said the upward arrow shows up on the dash as soon as the vehicle starts, and the vehicle revvs higher than normal and she is unable to go above 40-50 because it will not shift. i had always thought that the upward arrow indicated the car was in overdrive, but then again i dont know these vehicles well so any help/ideas would be greatly appreciated, thanks.