Why Does the Wiper Move When the Ignition Switch Is Turned On?

[DelWalter]

Turning on the ignition switch causes the wiper to move because a reserved position is designed. The wiper is designed with a reserved position: When the car starts or shuts down, the wiper moves slightly because a reserved position is designed in its travel path. After losing power due to the disappearance of oil pressure, air pressure, or electricity, the wiper returns to its original position. If the wiper was in use before shutting down and it moves slightly, this is normal. During normal operation, the wiper stops at a position approximately 5 cm above its usual resting place. Precautions for observing the wiper: When turning off, the wiper will go through a process of returning to its original position, which is why you see it move slightly. Additionally, if the wiper activates without being turned on, it might be due to a sudden connection at the wiper's joint. In this case, it is recommended to check the power connection point of the front wiper, which is usually located above the washer fluid reservoir.

[DeDonovan]

I found that the wipers inexplicably activate when turning on the ignition, which is usually caused by a short circuit in the grounding wire. I remember my car had the same issue last time—the wipers would start moving as soon as I turned the key. Later, it turned out that the wiring near the wiper switch had aged, causing the positive terminal to directly connect to the wiper motor, powering it when it shouldn’t. Grounding issues are often related to body corrosion or water seepage, especially during rainy seasons or in humid environments. If the wiper system control module fails, it might send incorrect signals triggering unintended actions. If not addressed promptly, this can not only drain the battery but also distract the driver while driving, particularly in rainy conditions. I recommend taking the car to a professional workshop immediately for inspection to prevent further damage to other components. After all, safety comes first—spending some money is always better than taking risks.

[RowanLee]

I once discussed a similar experience with my friend where the wipers would activate randomly upon ignition. He suspected it was caused by a short circuit due to a loose or damaged ground wire. Poor grounding can cause erratic current flow, directly powering the wiper motor without passing through the normal switch. This type of fault often results from aging wiring, corroded connectors, or improper modifications. For example, if wiring was tampered with in the garage and not secured properly, moisture intrusion can lead to issues. Prolonged neglect can strain the electrical system and even damage other components. Fortunately, the fix is relatively straightforward—my friend first removed the wiper fuse as a temporary solution, then had a technician use a multimeter to diagnose and repair the issue. Regular maintenance checks on wiring connections can prevent such problems—don’t wait until it’s too late to regret it.

[KiraRose]

The wipers activate on their own when the ignition is turned on, most likely due to a faulty switch or internal sticking. When the ignition starts and powers the system, if the switch contacts are stuck, they continuously send activation signals. A short circuit could also cause this, such as water seeping into the wiring and triggering false activation. Don’t underestimate this issue—it can unnecessarily drain the battery and even jam the wiper arms, leading to accidents. Prompt inspection is crucial. Start by checking if the switch shows abnormal heat or unusual odors.