Why does the slip light come on in a 1994 Infiniti Q45?

Well, I am not a mechanic but I own a 96 Q45 and experienced a similar problem. The warning light has to do with the traction control system. Your problem could be a number of things since the Q45 has so many sensors and relays etc. When I went to my dealership with my problem, the service advisor pointed out a black plastic box under the hood on the passenger's side close to the firewall. The black plastic box is attached to a silver aluminum box with a number of hydraulic lines attached to it. Remove the cover from the plastic box and you will see two relays inside. On the advice of the service advisor as a first step to solve the problem I replaced the two relays. That did solve my problem and that was almost 4 yrs ago now. The relays pull right out of their sockets and you just plop the new ones in. I live in Fl. but ordered my new relays from Infiniti of Scottsdale Az. because I could get them much cheaper there. They are called "Relay Assy-valve" Part# 47605-17V03 ($20.27) and "Relay Assy-Actuator" Part# 47605-17V10 ($19.28).

Hope this helps