I brought my car into pep boys to have my break.

I brought my car into pep boys to have my break pads and rotors changed because when I applied the break there was this grinding noise. After they put in the new parts I drove away only to discover the noise was still there. I went back to pep boys and they looked at the car again and informed me that I had let my breaks go too long and had destroyed my ABS and now I need to have that replaced. They told me I had to bring it to the dealer and it was going to cost me over $400 because they had to check all the wires to see what was broken. My question is, I did nit feel like I let the breaks go for that long. Also is this even a thing? If so, how much should it cost to replace? Thank you.