Please help, help help
Does anyone know what these relate to? I have searched the net and although they are mentioned a million times there is no indication to what part (s) they relate to and what needs to be done to rectify. Is this a secret to volvo or just beyond the realms of the average home mechanic? Also would these cause the car to go into limp mode when revs hit 2500?

P0144 O2 Sensor Circuit High Voltage (Bank 1 Sensor 3)
P0571 cruise control brake switch A circuit

Just in case these are beyond us, does anyone know of a reputable volvo specialist (not main dealer) in the west yorkshire area UK?