Jeep Grand Cherokee interchangeable computers

A 1994 is OBD 1, any model from 1996 or later will have OBD 2 diagnostics, and will not work with that vehicle. You would be limited to late 1993-1995 Dodge Ram/Dakota with the 5.2 as a *possible* replacement, or a unit from another Jeep with the same motor, which is actually quite a rare vehicle as most were the straight six motor. I say possible from the Ram/Dakota line as the Jeep systems may be using different coding/sensors than the Dodge trucks. If you can find a cheap unit at a junkyard give it a shot. But the best bet is a reman unit from the exact same year and model Jeep.