e36 ABS light on, have done basic tests

[tintop 10]

Right my gf's e36 328i has had the ABS light on for a wee bit. The ABS doesn't work, but the pump still cycles when you play with the relay. I have taken the wheels off and cleaned and checked the sensors. The fuses are all fine. The yellow ABS light still remains.

The only other thing I'm gonna do is pull the plug out of the ABS unit and check each sensor monopole with a multimeter and see if one is down.

Is there something I have missed? We haven't moved the car since doing these tests, does taking it for a drive clear the light if the sensors were just dirty?