Car won't turn on

It means you have "throttle-by-wire". That is a ridiculous system that replaces the very reliable and simple throttle cable with two position sensors and a very trouble-prone computer. (Ever hear of Toyota's runaway cars? You have the same thing). When there is any disagreement between the position sensor on the gas pedal and the sensor on the throttle body, the system goes to a fail safe mode which usually means you're walking. If you think you might have been pressing the gas pedal when you turned on the ignition switch, the problem might resolve itself by turning the switch off, waiting a few seconds, then trying it again. Some people might suggest you disconnect the battery for a minute to reset the computer, but be warned that will lock up all kinds of things including the radio. To tie you to the dealer, GM builds the Body Computer into the radio so you can't replace it. This is the type of business practices that keeps them profitable. Without the radio working, you won't have power windows or cruise control. All of the other computers on the car have to communicate with that Body Computer before they will turn on too. There can be up to 47 computer modules at last count.

If the problem doesn't clear up, have it towed to the dealer. GM is very stingy about making repair information and the needed software available to the independent repair shops. Only Chrysler, Toyota, and Hyundai put their customers' needs ahead of profits and make everything available to all shops. Hyundai's web site and software installs are 100 percent free.