What does DFF mean on a car?
2 Answers
DFF on a car indicates the wipers are turned off. Generally, the wiper switch markings on cars appear in the form of English abbreviations. The wiper switch markings on cars have the following meanings: MIST means the wipers make a single sweep; INT means the wipers operate in automatic intermittent mode; LO indicates the wipers operate in continuous low-speed mode; HI means the wipers operate in continuous high-speed mode. For most vehicles currently on the market, the wiper switch is located on the right-hand stalk behind the steering wheel, typically in the form of a stalk. The wiper stalk, much like the headlight stalk, is marked with numerous functional symbols. Although the symbols and their positions may vary across different brands, their functions are generally similar. When the rain is not too heavy and the windshield is not densely covered with water, you can set the wiper stalk to the low-speed mode, marked as LO. When the rain intensifies and the windshield quickly becomes covered with water, significantly impairing visibility, you should switch the wipers to high-speed mode, marked as HI.
I've been repairing cars for many years. The DFF on a vehicle generally refers to the diesel fuel filter, which is specifically designed to filter out impurities and water from diesel, protecting the engine from damage. If it gets clogged or fails, the car will noticeably lack power, accelerate as slowly as a snail, and is prone to stalling, especially when climbing hills or under heavy loads. Listen to the engine sound—if there's slight shaking or uneven acceleration, it's likely the filter is the issue. Diesel vehicle owners should pay attention to this. For city driving, it's recommended to check it every 15,000 kilometers; in dusty rural areas or construction sites, replace it more frequently, say every 10,000 kilometers. Replacing an original filter costs just a few hundred yuan, but if you wait until the engine fails, the repair bill could easily exceed ten thousand. As a side note, during regular maintenance, you can also clean the fuel lines, which can extend the DFF's lifespan and give you more peace of mind while driving.
