thats weird, maybe you've got a dodgy earth somewhere as they should all come on and then go off after a few seconds.

next thing i'd try then is disconnect all the sensors and with a multimeter check the resistance across each sensor. i did this on my brothers primera last week as thats got an abs problem and we discovered some twat removed the abs bulb. only reason it got through its last mot is because without the bulb lit you cant see where the abs bulb should be on the dash! i found that his front near side was 1.6 kilohms but the fucked one was about 30 ohms. that was confirmed when we put an abs bulb in and earthed pin 4 of his diagnostic port as that flashes the abs bulb in sequences giving fault codes all of which pointed to the high resistance sensor.

i dont think you can do that pin earthing trick on th emondeo though but certainly worth measuring the resistance accross each sensor. will hopefully indicate the faulty one.

oh and my bros car does the same as yours where the abs kicks in slightly when just coming to a stop.