I replaced the terminal connector with new pins and plug socket. Nothing changed. I bought X5 manual book and get the information of ABS sensors in the following.
pin1 pin2
L. Front Red Blue/Red
R. Front Yellow Blue/Yellow
L. Rear White Blue/White
R. Rear Green Blue/Green

P.S. just for beginners like me, the pin number (1,2,3) marked in the plug socket.