2. For a quick check, you can measure the thickness of the friction lining on each brake pad on top of the caliper body. If at least one of the linings is worn out, all four pads on that axle must be replaced.
3. For a more complete check, it is necessary to remove the pads and clean them thoroughly. This allows you to check the condition of the caliper and brake disc on both sides. More details about this are in chapter 9.
Warning: Do not swap pads to compensate for uneven wear as this may result in loss of braking performance.