In some wiper systems, how does the delay time respond to vehicle speed?

• A. Remains constant
• B. Decreases as speed increases
• C. Increases as speed increases
• D. Random

Answer: (C)

The main idea here is how speed-sensitive intermittent wipers adjust their timing. In systems that use a speed signal, the wiper controller shortens the interval between wipes as vehicle speed increases. This happens because at higher speeds rain, spray, and debris cross the windshield more quickly, so wiping more often helps maintain a clear view. The timer is effectively driven by the car’s speed input, so the delay between cycles decreases to keep visibility consistent. If the delay didn’t change with speed, or if it got longer as you went faster, visibility would suffer because the wipers wouldn’t sweep often enough to counteract the faster relative motion of water on the glass.