Hi Ive got a 2002 Jeep Liberty. The ECU is toast. Can I swap in a second hand one out of another truck or will there be pairing problems ? I have done this in my 94 Isuzu Trooper a few times with no problems but its a bit older and dumber, haha.

It will have to have your VIN programmed into it,more so if you have the OE alarm as it will not run.And yes the PCM must be installed to reprogram and at a dealership or shop that has the equipment to reprogram PCM's.

Dam, that is not what I wanted to hear, but thankyou for taking the time to reply