Does anyone else have this problem? First on my 2005 SL500, and now on my 2007 SL550, there is a "chirping" sound when you step on the brake. The 05 model was in the shop a couple times, then I think some sort of TSB fixed the problem. Now the 07 has been in the shop to check it, they ordered and installed some sort of bracket to hold a brake line, and now it has started chirping again! This does not come from the brakes themselves, but from the engine compartment, I think. I'm really getting tired of this, especially when it was an apparent problem on the 05 model, now carried over to the 07 model??

 

Mine did the same thing. It actually sounded like a plunger noise coming from the right rear. At first the MB tech's told me it was the lines running to the SBC system.
Eventually, a tech by the name of "Damaged" on the MBworld board helped me solve this issue.
The MB techs had to bleed the brakes and reset the computer...it has been fine ever since.

 

Thanks for the info. I had a service appointment for this past Weds, and on Tuesday when I had the car out a bit, the chirping had just disappeared! Strange.... I cancelled the appointment, but told them if it happens again, I would be in for them to fix it. Will suggest bleeding the brakes as you said.

 

there was a bulletin about that noise and the "fix" was to depress the brake pedal fully and very quickly like 30 times. also a mod to the lines to the brake unit to help quiet the noise.