ABS / Brake Replacement

[koban]

Hi guys,
Found out my three lights on the dashboard are due the the abs sensor. If i remove and clean this will it be any better as we have had a lot of snow recently, also i have check brake lining come on now and again, will this affect this sensor??

When i replace the rake pads will i have to replace the sensor as it only appears now and again, so will new pads move it away from the disk??

Any help would be great. I have the 4.4i 2000 with 130k on the clock. Never missed a beat!!