I dont know!!! It only appears in my computer...ANti-Skid Service requiered..It should be other codes ...if so..how can I found them??

Does anyone can help me with that problem??? I need to change my ABS HYDRAULIC MODULATOR....BuT I just need to know if I need a new one......or I cand use a second -hand one too????....If anybody have any information please tell me anything you know about it!!!Rgds Dan