Q: Does the OBD system use more than lights to communicate with the driver?

故障指示灯灯（MIL）和可听见警报是当前唯一的手段诊断（OBD）系统可以通知驾驶员的任何问题，这些问题会对发动机或其他电子控制系统的操作产生不利影响。

The MIL, or检查引擎灯, being illuminated doesn’t automatically mean that your car is about to break down. It does mean that the Powertrain Control Module (PCM) has detected a failure that is causing your tailpipe emissions to exceed acceptable limits. Basically, the MIL is telling you that you are polluting the air. You need to have a trained technician check the OBD system to determine what issues the PCM has detected and to have them addressed. Not only will your engine run efficiently, but you won’t be polluting the atmosphere, either.