1999 Chev Venture ABS/Brake Light

1999 Venture ABS and brake lights are on? Went to local repair shop , code for left front wheel hub sensor. Replaced sensor hub and light remains on, light will clear with foot on brake pedal while starting engine, as soon as brake pedal activates ABS system releasing of brake pedal and activating brake switch, a series of clicking sounds comes from the control module cover. Is the problem with the modules, the pumps or what????? Taking the van to a ceritfied GM dealer for more investigating of codes.
Does anyone have a similar problem or solution???
:banghead:

the clicking you are hearing is the ABS valve going through its self check, it fires all the solenoids and the pump motor at each key on. Normally this occurs at some vehicle speed 5 to 10mph, so the driver does not hear it. I would question the Vehicle speed sensor if occuring differently.