How can you detect your indicator is defective?

Your answer is correct because there are two main ways to detect a defective indicator in a vehicle according to German traffic rules. First, if the indicator control lamp on the dashboard flashes faster than normal when you activate the indicator, it usually means one of the indicator bulbs is defective or not working, as the system detects a difference in electrical resistance. Second, performing a functionality test before moving off, by briefly switching on the indicators and checking if all the lights work properly, is a recommended safety measure to ensure all indicators are functioning. The third option is incorrect because the indicator control lamp never illuminates red permanently; it flashes green when indicators are working correctly.