1993 Grand Cherokee 5.2 not getting power to fuel pump

check all other fuses and relays, especially the pcm relay. inspect the wiring to the pump. get a tester and trace the wires. check for 12 volts at wiring harness to the pump.

Where is the pcm relay located?

Not sure on your model, but it shouldn't bre too hard to find. Is there a power panel under the hood? Possibly in the glove box? Also, it wouldn't be a bad idea to scan the computer for codes whether or not you have a check engine light or not. If there is no power to something, check every fuse you can find.