I also have this problem. I am in the driver's seat and when I get in, the engine is already on (the M key is already green), but I can't do anything, can not press any number buttons. Also, if I am a passenger, the AI driver doesn't drive. In addition, one of the trucks is sometimes flipped on its side or tilted so not all firefighters can get in. I have tried to reinstall already and it did not fix the problem. Please help and thank you!