Archived ABS / Brake light on

[jlopezpe]

I have a 1990 D 250, 2 WD. The ABS / Brake light comes on, but when I pump the brakes I feel a pop through the brake pedal and the lights go out. It seems to happen when I apply the brakes slowly. I blead the brakes at the ABS module and it seem to improve some, but not completely. The fluid level is correct.