Should they squeak? No. on a bike if they squeak you need to lower the break pads so they are inline with your wheel, if you do this and it still squeaks you need new wheels
Can they? Yes, if they are in contact with the rotor (or drum) even when the brakes are not activated. (Does the squeaking change or worsen when you do brake?) Note that this will cause both a significant loss of fuel economy and a rapid deterioration of brake pads and rotors. Look for grit or stuck calipers, and, failing that, consider the possibility of partially activated parking brake shoes (depending on your vehicle) or wheel bearing damage. You could first try applying some graphite based lubricant to the *back* of the brake shoes (never a drop on the surfaces which contact the rotor!!)-- this is sometimes supplied with the pads by the manufacturer so the clips won't squeak against the housing.
Could be a high spot on the disc or if still rust lip on outer edge rotate disc and place flat edge of screwdriver to edge of disc this will dislodge lip clean away all waste when complete ansre assemble brake caliper (all ways use Eye protection when carrying out this job )
They are not supposed to make noise unless abs is on. If you are talking about the squealer tabs on the pads, they will some times squeak when you are off the brake and go silent when you brake.
need new rear brake pads.
Brakes will squeak when the brake shoes vibrate on the rim of the wheel as they grab. As the rim rotates, it will twist the brake shoes so that only the back of the show touches the rim. To fix this, you need to make sure your brakes have what's called "toe in". Essentially, the brake shoes should be angled in such a way to where the front of the brake shoe touches first. Then, as the rim and brake shoe meet, the brake will flex in and the shoes will grab flush into the rim and not squeak.
applying the brakes
The brake pads have a squeeker plate on them. If you recently had a brake job, they removed the plate and did not replace it. I
faulty master brake system
The brake pad squealers are warning you to have the brakes serviced soon.
Occasionally, new brakes will squeak or squeal for a short time as the pads get "bedded in." But in general, brake pads that are properly installed should not squeak, especially with new rotors installed at the same time. Usually, one of the following components is used to PREVENT squeaky brakes: --brake pads with built-in shims to prevent vibration that causes squeaking. --brake pads with external shims (usually thin sheets of metal) between the pad and the rotor. --lubricant OR adhesive between the brake pads and the caliper to prevent vibration. Auto manufacturers specify what anti-squeak measure(s) should be used for brakes of specific vehicles. If whoever installed your brakes didn't follow the correct recommendation, that could be why they squeak. It's also possible, but less likely, that the wrong pads were used. You should take it back to the shop that did the work and ask them to do it correctly.
worn pads change your brake pads and get your rotors machined while your at it
Warped brake rotor(s). Brake pads and calipers should also be inspected.
STICKING BRAKE CALIPER
You use them by applying the brakes.