If any one can help me that will be great

Some one ran up the back of me and popped out my parking sensor

So I took it out as the plastic part came off. So I fixed it all up and plugged it in
But not they come on and stay on then go off but the light what you can turn them on and off with is flashing.

If any one can help that will be great.

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bmw x5 2002 3.0i (E53)

stereo has sat nav and phone