Clean and check the brake caliper and dust cover
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2006 Volvo S80, 2005 Volvo S80, 2004 Volvo S80, 2003 Volvo S80, and 2002 Volvo S80. However, it is still accessible from the selected car via links, so may be relevant.
Clean and check the brake pad mating surfaces in the brake caliper and caliper holder.
Clean the sliding pins using a steel brush.
Check the piston dust boot. Replace the dust boot if it is damaged.
NOTE:
If the dust boot is damaged dirt may have penetrated the cylinder. The brake caliper must be reconditioned. See Reconditioning front brake calipers
.