My W212 is causing this squeal/squeak noise ONLY when at SLOW speeds and it disappears if I touch the brake the slightest. Brake pads are completely fine and have life. What could be the issue.
In the end of the video I pressed the brake slightly and the noise disappeared.
Thankyou

95% chance it's brake pads contacting brake rotors in not an entirely proper way.

> Take a PICTURE of the rotors...
Ritors need to be smooth, not grooved

> Check how big is wheel bearings freeplay!
Loose bearings allow rotors to wobble

> How long ago since pads installed?
Pads need 500Mi to become true with disks surface

> Silicone lubricated slide pins ?
Calipers need to easily self-center over rotors.

> Who works on this car??
Someone needs to be in charge of maintenance.

I checked the rotors they seem fine! What causes and how to fix the brake pads contacting the rotor ? As you said in the first point. The sound is coming only from front right side wheel (driver side).

Sounds like this? https://mbworld.org/forums/w213-amg/...cabriolet.html

If so, my family member's C238 E 450 coupe has it too, I understand yours is a W212 but it was the carriers or something, more info in the thread.

As you've discovered: "the sound goes away when you press the brake pedal".

Beside the preliminary pointers, I can add that the floating calipers use an anti-rattle spring that torques the caliper at 90° against slides. These springs are way to strong. They prevent caliper from sliding properly to get pad surfaces aligned well with rotor.

Simpler version:
Install new genuine rotors + genuine pads to solve your noise issue.

Yes, the sound in your relative’s vehicle sounds very similar to mine! But was it the same problem as mine like only at slow speed and in front and would disappear even if brake is applied the slightest? I am still not able to sort it out till date.

Sounds like a classic case of brake pad vibration or glazing to me, even though your pads still have life left. Since the squeak disappears the moment you touch the brake, it’s likely one of these:

1. Brake Pad Wear Indicators – Some pads have wear indicators that can cause slight squeaking at low speeds before they hit full wear. Even if they look fine, check if the indicators are making contact.
   
2. Glazed Brake Pads or Rotors – If the pads or rotors have developed a smooth, hardened surface from heat, they can cause a high-pitched squeal at slow speeds. A light sanding or resurfacing might help.
   
3. Lack of Lubrication on Contact Points – The brake pad backing plates and caliper slides should have a thin layer of brake grease (not on the pad surface, of course). If they’re dry, the pads can vibrate and cause noise.
   
4. Loose or Worn Anti-Rattle Clips/Shims – If the pad clips or shims are loose, missing, or worn, the pads might be vibrating slightly when not under braking pressure.
   
5. Dust or Debris Build-up – Sometimes, brake dust or small debris gets trapped and causes squeaking. Blasting the brakes with compressed air or brake cleaner might help.
   

You could try removing the pads, lightly sanding them, greasing the contact points, and re-seating everything. And I hope i've helped you.