Just went through replacing the old filament bulbs with LED. I don't know if Volvo (and which) is using the same sockets as Saab - at least my 9-5 employs bulbs with T3, T4.2 and T4.7 sockets and I haven't found any smart LED which is making the change a little bit complicated as you have to take care of the proper polarization (there are no markings on the sockets or the settings) and you will most likely not being able to dim the panel anymore unless you replace the dimmer with a DIY solution.