What Causes Weak Wiper Performance?
3 Answers
Weak wiper performance is typically caused by excessive friction between the wiper blade and the windshield. It could also result from a malfunctioning wiper motor or increased resistance due to insufficient lubrication in the linkage mechanism. The wiper system is an essential device for every driver during rainy conditions, ensuring the front windshield remains clear of water to maintain visibility while driving in wet weather. The power source of the wiper comes from an electric motor, which serves as the core of the entire wiper system. The quality requirements for wiper motors are exceptionally high, as they utilize DC permanent magnet motors. The wiper motor installed on the front windshield is generally integrated with a worm gear mechanism, which functions to reduce speed and increase torque. The output shaft drives a four-bar linkage mechanism, converting continuous rotational motion into a side-to-side oscillating movement.
Last time my car also had weak wiper issues, and through troubleshooting I found several possible causes. Motor aging is the most common - over time it naturally loses power. When I popped the hood and touched the motor location, it felt abnormally hot, so I promptly replaced it. If the wiper arm joint rusts and seizes up, it can also cause dragging - try applying rust remover and rotating the joint. Loose mounting nuts will make the wiper wobble, dispersing the force - tightening them shows immediate improvement. Poor wire contact can also cause weak power, especially with oxidized/blackened connectors - just resecure them properly. Those who park under trees should pay extra attention to cleaning wiper blades, as bird droppings increase resistance and make wiping laborious - regular cleaning is essential.
From an experienced driver's perspective, weak wipers are mostly due to mechanical or electrical issues. First, simply operate the switch and listen for the sound of the wiper motor. If there's a clicking noise, it's definitely due to worn gears inside the motor. If there's no response at all, check if the fuse is blown—replacing a small fuse can easily solve the problem. Incorrect wiper arm angles can also cause sluggish movement; manually adjusting them back to the correct position will make them work immediately. In long-term humid environments, metal parts are particularly prone to rust and seizing—a few sprays of lubricant will restore normal function. Low voltage is equally important; I've encountered cases where insufficient battery power directly caused slow wipers, which fully recovered after charging. It's recommended to regularly apply windshield degreaser to reduce resistance, protecting the wipers and making them easier to use.
