The keyless access system used in the Cadillac XLR and STS and Chevrolet Corvette does not use a traditional key for door locks or ignition. Instead, the driver carries a transmitter fob. When the vehicle senses the presence of the correctly coded transmitter fob, the doors can be opened. With the transmitter fob inside the passenger compartment, the engine can be started by pressing the START button on the instrument panel.

Ignition On, Engine Off Mode

There may be times, such as when you are performing diagnostics on the vehicle, that you need to have the ignition turned on, with the engine not running. In this mode, all modules are powered up and communicating on the serial data line.

TIP: This information is covered in SI. Follow this path: Accessories > Keyless Entry > Description and Operation > Keyless Entry System Description and Operation > Ignition On Engine Off Mode

- Make sure the transmitter fob is inside the passenger compartment.

- Depress the brake pedal.

- Be sure the transmission is in Park or Neutral.

- Press the ACC button and hold for 5 seconds. The instrument panel will light up and the ignition will be turned on, but the engine will not start.

- You must press ACC again to turn the ignition off.

TIP: If you press the ACC button only briefly, the accessory mode will be turned on. This is not the same as turning the ignition on.

TIP: Programming cannot be performed in the Accessory position.

TIP: Retained Accessory Power will function for 10 minutes after the ignition is turned off, or until a door is opened.