Tried a search, didn't find anything-

2003 discovery, v8, w/ ace. I have a very,very soft noise, almost a beeping or an electronic hum, coming from the abs modulator box. Follows a pattern of about 1/2 second on, then 1/2 sec off, repeating. This is continuous - if the engine is running, off, even if the key is removed. Having no brake problems, lights, or battery issues. Any ideas?

 

Don't worry about it, can't technically explain it, but its normal. Mine's been doing it forever.

 

Have similiar noises....... never had any problems with the brakes, ABS, etc. I attribute it to a disturbance in the force.... and have never found a 'fix' for it, or even reasoning as to why it needs to be fixed.... wierd

J

 

I believe that there is a TSB on this and that the dealer can remap the SLABS unit to make it stop.
Itcan run the battery dead if not driven for awhile.