I bought a 2010 Fiat 500 1.2 pop 5 weeks ago. Since having it I have had a new clutch and gearbox bearing done and two new front tyres. I drove through a huge puddle a few nights ago and when I drove the car the next day it sounds like some scraping going on with the brakes. The brakes passed its MOT 5 weeks ago. Could this slight grinding have anything to do with the water I drove through? Thank you in advance.
Vehicle brakes have been designed to allow for operators driving through deep water. Your vehicle likely has disk brakes, which are made of a steel alloy that rusts if you look at it crossly.
It sounds from your description that your brake disks have collected a bit of overnight rust from being wet. The scraping sound is the brake calipers scuffing off the rust, which is also provided for in the design.
I have a vehicle that is rarely driven and the disks will collect surface rust which is shortly scuffed away in normal braking.
I use the term "collect" but the reality is that some of the surface is converted to rust by exposure to the air and to moisture. Rust never sleeps.
More extensive reading can be found on the 'net, but the results of my search provide the same conclusion. Here's one with a bit of commented discussion.