I have a 1941 with the security licence. I also bought a 1941W cheaply off eBay. It only had a base licence. I tried swapping the wireless module from the 1941W to the 1941. The 1941 would not recognise it and threw up errors. Both have the latest IOS and bootrom. Any ideas as to why the 1941 would not recognse the wireless module?
I doubt that that will work. The PID is burned into the router and adding the module won't change the PID. I expect that IOS will only activate the wireless module in a W router with the wireless PID. That's probably intentional because of regulatory implications for the products. In any event I'd expect to see something in the logs when it boots up.