[s-cars] urs4 remote lock feature

[Rit Bellis]

I have a 93 urs4 that does not appear to have the infrared locking system working.  I replaced the batteries in my key, but nothing has changed: point key at remote reciever outside, nada.  How do you diagnose this, and perhaps more importantly, what should the system do if everything works?  Since mine never has, I am clueless where to start.  (I checked the knowledge base but couldn't see if the few posts there were for s4.  Thanks!