It doesn't have to be inaccesible, you just have to have it unloaded and in a case. The ammo or mag can even be in the same case. Plus I believe the law allows a center console to count as a case, but it still has to be unloaded. But again, the mag can be in the console too.
I live in IL and have a non res UT license. I carry whenever I go to my folks' in IN. I keep it unloaded and in the console until we cross the state line, then load up. I just put the empty holster on and have a cheapo Uncle Mike's that I keep it in when I am not carrying. First time we stop in IN it goes from the console to my belt.
I have a small safe in the car for if we stop in IL before we hit IN. I never leave it unattended in the console.
BTW, I don't know the Chicago laws, that's just for the rest of the state.