Brake fluid / warning lights

Today, I first called Toyota Customer Experience Center. Rep was courteous, but couldn't/wouldn't tell me if booster failure could lead to fluid loss. Next called dealership service dept. Service advisor told me "bad or funny braking" might result, but not fluid loss. Interestingly, she advised: "If it was me, I'd just watch it", as warning indicators disappeared with fluid replenishment. I then drove it to my local service shop. Owner offered to look at it tomorrow with me, w/o wait - he was down a few men today (and today is a Monday). I said fine; I'll report back tomorrow. Fluid level seems stable short term.

 

As owner and I walked over to the car, which had just gone up on the lift, I began to tell him that the fluid level had dropped this morning when I checked it (prior to driver side door opening). Before I finished, we arrived at the rear wheel whose caliper had been replaced. I don't know who was more surprised. He announced "you got a leak!" (We had both agreed yesterday that there must be a leak).

Lots of fluid visible. Quite striking. The entire visible caliper and inward-facing portion of wheel covered w/fluid; much of inward-facing portion (would a technican use the phrase "medial aspect"?) of the tire also fluid coated. I say surprised because the fluid level had dropped only 1/8 to 1/4 inch this am from yesterday am (evaluated under same conditions).

He instantly told me everything was covered under the 1 year warranty he issued 10.5 months ago. When I picked car up tonight, he said culprit was "a defective seal in back of caliper".

Mendel: I did spin said wheel when it first went up on the lift - it did at least one and a half full revolutions. The owner was amused that I appeared to not have full faith in the original installation, so I stopped watching closely once it was clear that it could spin freely. But I didn't think to try to be present to recheck right after after new caliper was installed today.