abs problem

[nis]

My car is 220 cdi diesel year 2000 ,one day when my leg was on the pedal of the brake suddenly had two warning light , one bas/esp and the other abs that stay permanently.
So from this moment the abs stop to operate , but the problem is that a little motor near the computer unit start work continuously even if I stop the car and put out the key.
It never stop unless pull out the connector of the computer unit .
I want to mention that four month ago I replace computer unit and it cost me about
900 euro .
if someone or anyone have any information why it happened and what I should
do to fix it , please tell me urgent because I am very desperate.