2004 Jeep Grand Cherokee - Won't start

Hello my Jeep won’t start , I tested fuel pump it works but doesn’t turn on while trying to start . The Jeep also doesn’t have spark while trying to start eaither . I replaced the fuel pump so it’s new and I can’t get a fuel reading it says it’s on e but I have a full tank . Also I have noticed that the key security light comes on and stays on the whole time while trying to start unsure of the problem , not sure if it would be because of the new computer that was put in a couple month ago it has now been sitting for a while can’t get it started

A few simple questions . . .

WHY was the “computer” replaced . . . I presume you mean the engine control computer?

Did it EVER start after replacing this computer . . . ?

how have you determined “doesn’t have spark” . . . did you use a spark tester?

why did you replace the fuel pump?

do you have multiple keys? . . . if so, try them all

I got the truck from my father he had it at a shop and it was sent there because it kept stalling while driving , they told him it was the engine computer so he had it replaced the shop then said it wouldent start that it was out of fuel and that the pump was bad so I replaced the pump without checking power to it sadly . Once new one was in I tested old one for power and it worked but no power to the connector which the pump connects to . I then replaced the crank shaft position sensor because I’ve heard of that being a reason for no start , after that and still no start I checked for spark the way I did was pulling the coil pack out and putting a spark plug in it having it touch metal looking for spark and didn’t get any even with a new plug . I after realized that the key light was solid on it was probably on the whole time and it never dawned to me to check it when we picked it up from the shop . I have ran out of options and things to think of to do to fix it , but still trying to see if I can find out before sending it to a dealership and spending a good amount of money . Thanks for the advice

A used Powertrain control module won’t work, the key data from the immobilizer module won’t match, engine won’t start. If you have the original PCM install it, if not you will need to get a remanufactured or new PCM. After installing the PCM the VIN and secret key data must be transferred from the SKIM module to the PCM.