Here's how I know this....last year I we had a van that had a faulty steering column lock solenoid. I have a thread on the swap somewhere here. We had spare parts from a truck one of the guys smashed and totalled. I thought it would be easy enough, but quickly discovered the ignition switch module wouldn't communicate with the "new" steering column. Easy enough right? Just swap out the ignition switch from the other truck. Did that, now the truck wouldn't start or crank or anything. Thinking the PCM wasn't happy with my "imposter" parts, I then swapped out to the matching PCM. All is well, or so we thought...it wasn't long before the truck got an ESP light. I didn't think much of it being related, just another problem ya know. The guys drove that truck for 9 months this way. First start the truck, all is fine till you make a left turn then the ABS would get stupid, right front brake would try to lock up for a second, then the ESP light would come on. Again, drove the truck this way and just dealt with it. Finally, about 3 weeks ago we caved in and took the truck to the dealer, KY jelly in hand. Our scanner never showed any codes other than the ESP problem, but their scanner came up with 3 pages of codes stored deep in its abyss. All this stemmed from the steering column swap. Basically, all these modules in the vehicle communicate to each other electronically. When we installed "foreign" parts from a donor truck, the vin's didn't match up, and created communication problems. Nearly all the modules, and electronic components with some sort of circuit card are electronically VIN - ETCHED from the factory. Once this is done, that VIN can NOT be erased, it's like gouging your name into it. Additionally, we found that the gage cluster had to be swapped out because it's electronic VIN didn't match the PCM. The gage cluster is the second largest brain in the truck. No, they couldn't use the gage cluster out of the donor truck because there would still be certain conflicts with certain other modules. So we had to pay for a new cluster, $500 something dollars, and $600 something for labor.
Here's my take on this, if its got a module on it and it communicates with the cluster or PCM, take it in. No, we didn't save a dime by swapping out the used steering column, ignition switch, and PCM. It cost us $4,000 to get it all sorted out.