They are under the fusebox but to access them, all relays underneith, accessed from under the dash must be removed, then the upper fusebox cover is removed, the fusebox is unscrewed (4 screws plus the 4 that hold the wire loom covers on) and then the fusebox is carefully lifted upwards about 6" to access the 4 crimp connectors. The 4 crimp connectors are cut out and it's best to just splice and solder those wires rather than re-crimp them.
Now, before you do all that, check for ABS codes because that cure will only work if you have FRONT ABS sensor codes. Do make sure that the battery is disconnected.
IF you have either REAR ABS sensor codes (usually RR) or pump motor codes yet the pump works, THEN it's a bad ABS control unit.