[Big Sarge]

Does your jeep have a grey or black key? The grey key is a sentry key. If you have grey it is going to require a new PCM (I'm almost sure) but if it is the black key then you can get a used one. Has to be the same year, engine size as well as same transmission.

 

[Digger84]

First don't put too much stock in dealer diagnosis

Next if you buy a PCM you need
Also a tj not from a Cherokee or grand
Same engine
Same tranny
Same year
Same calif vs federal emissions
Finally and most important it must not have come from a vehicle with sentry key unless you also get the chipped key that was used in that vehicle and preferably at least two of the chipped keys that were used

After all that you still will have wrong vin stored in the PCM and you may or may not find your cluster odometer reading is completely changed

Best bet if and only if you are sure the PCM is bad and it is not an easy work around like a external voltage regulator or external 5 volt power source is to have your PCM repaired

Cheeper and no comparability issues