What Causes One of the Car Snail Horns to Stop Working?
4 Answers
Car snail horns may have one working and the other not due to the following reasons: 1. Poor sealing leading to moisture: The horn is internally sealed, but if the sealing is not tight, moisture may enter during car washing or water vapor may be present in the internal air space. This moisture can easily cause the contacts to become damp and fail to function properly. 2. Poor contact at the electromagnetic coil terminals: Some horns have electromagnetic coil enameled wire terminal connections made with aluminum metal rivets instead of secure soldering. If the insulation paint on the enameled wire ends is not properly removed or the rivets are not tightly pressed, poor contact can occur, leading to malfunction. This issue is due to the horn's quality and cannot be repaired; only replacement is possible. 3. Contact point erosion: Prolonged use of the horn can cause the contacts to erode, creating impedance. This weakens the current flowing through the electromagnetic coil, reducing the electromagnetic force and preventing the armature from properly vibrating the diaphragm. This results in a hoarse sound or complete failure. However, when the horn is pressed repeatedly, a momentary strong current can still pass through the impedance, allowing intermittent operation, hence the sporadic functionality.
I've encountered this issue with my own car as well. Usually, when one side of the snail horn works while the other doesn't, it's mostly due to loose or rusted wiring connections. Last time after washing the car, the horn on the passenger side stopped working. Upon opening it up, I found the connector was full of water stains. In such cases, don't rush to buy a new horn right away—try spraying some WD-40 on the connector to remove the rust. If you take it to a mechanic, they would typically use a multimeter to check if the circuit is intact and whether the voltage is sufficient. Another possibility is a problem with the horn relay. That little metal box controls both horns, and if the contacts are burnt out, it can easily cause one side to stop working. This issue is more likely to occur when driving in rainy weather, so it's best to periodically open the engine compartment to check if the horn connectors are secure.
Last week, my neighbor's car had the same issue—the left horn was completely silent. There are three common causes: the horn itself is broken (if the electromagnetic coil burns out, it won't make a sound); wiring problems are more common (rats chewing wires or oxidized connectors); and then there's the fuse acting up—though single-horn fuses are rare, some models do have independent ones. For DIY checks, wear gloves. First, press the steering wheel to listen for a clicking sound from the relay. If there is one, you can pretty much confirm the issue is with the horn. Replacing a snail horn is actually quite simple—you can buy a pair online for a few dozen bucks, remove the front bumper, and install it. The key is to correctly identify the positive and negative wires to avoid reversing them.
Veteran drivers know that when one side of the horn stops working, it's usually due to poor wiring contact. Snail horns are located inside the bumper, and their connectors can loosen over time due to bumps, especially if the wiring has been modified, making them more fragile. On the circuit, the two horns are usually connected in parallel, so it's rare for both to fail simultaneously. First, try shaking the wiring to see if the sound returns. If not, check if the relay contacts are carbonized. Another possibility is that the waterproof rubber sleeve is damaged, allowing water to seep into the terminals, which is especially noticeable during the rainy season in the south. If you're not comfortable handling it yourself, taking it to a repair shop to lift the car for about ten minutes should do the trick, with labor costs typically just a few dozen yuan.
