Sorry I'm keyed. Found this but again not sure myself.
ACC/ACCESSORY (Amber Indicator Light) : This mode allows some electrical accessories to be used when the engine is off. With the ignition off, pressing the ENGINE START/STOP button one time without the brake pedal applied will place the ignition system in ACC/ACCESSORY. The ignition will switch from ACC/ ACCESSORY to off after five minutes to prevent battery rundown.
Service Mode This power mode is available for service and diagnostics, and to verify the proper operation of the malfunction indicator lamp as may be required for emission inspection purposes. With the vehicle off, and the brake pedal not applied, pressing and holding the ENGINE START/STOP button for more than five seconds will place the vehicle in Service Mode. The instruments and audio systems will operate as they do when the ignition is on, but the vehicle will not be able to be driven. The engine will not start in Service Mode. Press the ENGINE START/ STOP button again to turn the ignition off.