In the simplest fashion it takes an offline signal and drives a set of white LEDs with no dimming.

最简单的台灯就是接到离线信号后点亮一组不带调光功能的白色LED。

youdao

It's only the piercingly bright RGB LEDs built into the steering wheel that give you a clue something is amiss as it drives across the show floor slowly -- that and the fact that there's nobody sitting behind the steering wheel.

ENGADGET: Nissan NSC-2015 self-driving car with LTE and smartphone connectivity (test-ride with video)