2000 Safari Brake Failure

I have brake failure when Im' applying the brakes and hit a bump at any speed. I do not losse the pedal they just don't seem to work.If I let off and reapply there fine.I saw another post that didn't go into detail or have a response. Any help would be appreciated

When this happens:
Does the "BRAKE" light or the "ABS" light on the dash come on?
Do you hear a rapid "clicking" or "buzz" sound from under the vehicle, (rear wheel ABS working)
Can you hear/feel the ABS pump when the front wheel ABS is working?

No lights come on, have not heard any noise,pedal feels different not soft just like being on ice.not every bump,not sure if it is when I hit a bumb on one side or the other

Did you check the brake fluid?

According to TSB 02-05-25-006B, if these symptoms are at low speeds the front wheel sensors pick-up coil surface and mounting surface need to be thoroughly cleaned. The sensors can be checked by removing the harness connector and ,using a DVM, test the sensor terminals for 350 ACmvs while spinning the wheel at hand speed.