Do you have to bleed the rear brakes of a 2001 Volvo S60 after replacing brake pads If so where is the bleeder and how do you do it?

There should be no need to bleed the brakes after replacing the rear (or front) brake pads. Make sure you place a rag around the top of the fluid reservoir to catch any excess as you press the pistons back into the caliper body though. If the brake pedal has gone spongy after pad replacement this suggests that the piston seals have failed or the caliper cylinder facess have corroded. On mine the bleed nipples are on the caliper body.