ABS brake light, traction and no hill assist?

I pulled all the sensors and blew out the hole and sprayed electrical contact in each one. Went off until I restarted it. Took each one off again, turned the key on and tested each corner, 11.8v going to each sensor. Did the Ohms test on each sensor in and out of the car and all four say open? Could that be? Hooked up the meter to the meter, set to AC volts, spun each corner, all four readings zero. Made a wire harness to hook sensor to car and attached my meter to the exposed wires, turned the key on 11.8v at each corner, turned meter to AC v and I had 24.5-8v? I have no idea where to go from here, help and thank you!