99 sunfire 2200, stock

Everything works great, until a rainy day. Stopped at light and ABS come on (not the light, the system). Since then, the pedal is squishy to about 3/4 of the way down, and only the front driver's side brake works at all. ABS still works on this one brake, but there is no ABS light or brake light on the cluster. Have no idea what this might be.

Yes I did search for this. Used to be a Probetalker.

Thanks a lot guys. Found out a drum piston fell out. The adjuster was out of whack. Replaced the ABS module for good measure.