Answer:
The statement is false.
Explanation:
When you stop your car, you should use your signal lights (indicators) to indicate your intention to stop, but the timing of the signal is not specified as "3 seconds before starting to stop." Typically, you should activate your turn signal a reasonable distance before you intend to stop or change lanes to notify other drivers of your intentions. There's no universal rule about a specific number of seconds in advance for signaling a stop, but it should be enough to give other drivers adequate notice of your actions.