T660 ABS tractor ABS light

OK....so I've done my due diligence in searching the interwebs and this site but can't seem to find the answers I'm looking for.

Situation is this: 09 t660
The tractor ABS light is on and constant. This just started after a particularly hard rainstorm. Cruise doesn't work, (even parked to keep oil pressure up), and jakes operate as though I've activated the brake switch. What could cause the computer to believe I'm applying the brakes when I'm not? And why is this causing the ABS light to come on?

I've tried pushing the ABS test button on the kick panel but it isn't doing anything.

 

Update: high idle works with parking brake released but not when applied.

 

Airlines would affect the tractor system?