you will need to use volvo scan tool i see that problem many times at times problem is just computer need to be reset is like frozen or you can have fault in different computer like abs or transsmision and if you using volvo scan tool it tells you to check in transmission fault codes or abs module or if no fault code at times you will need ecu reflashing with new software
Technician
10 Years Volvo Master Cerified Mechanic ,ASE Advanced Certified.I'm in Chicago area