So apparently Jeep has a secret they've been keeping from us....... A single fuse cure all for what's ailing your '97 XJ....... It's the unused "F-10" fuse slot in the fuse block. Users manual labels this simply as "open" with no fuse in the slot.
I had a '98 here that was setting 3 codes for no reason: p1491 Radiator Fan Relay Control Circuit, p0645 A/C Clutch Control Relay Circuit, and p0443 Evap Purge Control Valve Circuit. All components were testing normal and working except that the A/C clutch wouldn't work.
Kiefer spent 5 min. searching

and found a post about thhe Evap Purge code which said to put a 15 amp fuse in F-10.......This thread:
http://www.naxja.org/forum/showthread.php?t=79134&highlight=P1491
That fixed all of it........

No..... I'm not kidding.
The BOR rig also had an empty F-10 fuse slot and promptly received a fuse...... Tomorrow will tell........