Problem began with brake fluid leaking out from under cap. This left dirt always around fluid reservoir. After each oil change by the dealer, I noticed the brake fluid never was refilled. As service mgr. about this pointing out that the servicing tech did mark on the check sheet that he did service all fluids & the brakes. Last wee's visit to dealer pointed out that brake fluid was now below the seam in the reservoir or half ways between the MAX and the MIM lines. The tech this time spotted bubbles in the fluid in the reservoir. They removed all the fluid, bleed the system, refilled the system and told me a new reservoir & cap must be ordered. In two days the new parts arrived & were installed.