First check the fuse to see whether the fuse, and then pull off the horn plug, using a meter measurement in the horn switch when there is electricity.

首先检查保险丝看是否熔断，然后拔下喇叭插头，用万用表测量在按喇叭开关时此处是否有电。

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Break the contact by switching off the current or meter if it can be quickly reached, if not remove the plug or wrench the cable free.

如果电源能很快的够到，则关掉电源，防止再接触，如果不能的话，就移开插头，或者扭掉电线。

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Turn on the phase meter and touch each plug of the socket;

打开相位计，并碰触插座的每个插孔；

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To find the energy hogs, you simply plug each appliance into the meter in turn, and then plug the meter into the wall socket and leave it switched on for a fixed time.

ECONOMIST: The much-talked-of smart grid prepares to enter the home

We can imagine the day when you'll be able to charge the battery on your plug-in hybrid car at night, because your smart meter reminded you that nighttime electricity is cheapest.

WHITEHOUSE: President Obama Explains the Smart Grid and Economic Recovery | The White House