P1493 is a manufacturer specific code. The various data bases on the internet say that for Chrysler, it is battery temperature sensor voltage too low (which I take to mean that the sensor is defunct). But 1996 was a long time ago and it was the first year that OBD2 was required and the chances of it being a computer bug or having some other meaning that never got documented are fairly high. These manufacturer codes are sometimes concocted by sticking a 1 in front of some related required code. In this case, that’d be likely be P0493 – fan overspeed.
Maybe if you fix the P0117 problem, the P1493 will go away. Keep in mind that many DTC codes don’t clear until no problem has been seen for some number of “drive cycles” and that the definition of a “drive cycle” varies from vehicle to vehicle.