The other way to be zapped by a car is to inadvertently act as a ground for the ignition system, which can be painful and dangerous. The other electrical systems in most cars aren’t dangerous or capable of shocking you, with the exception of electric and hybrid vehicles.
The How and Why of Automotive Static Shock
When you touch a car door handle, door, or another metal surface and feel a shock, the cause is the sudden discharge of static electricity. This is the same phenomenon behind the trick of shuffling your feet on a carpeted floor before touching another person to shock them or magically sticking a balloon to something after rubbing it on your sweater. Static electricity is generated when an electrical charge builds up in one substance due to rubbing against another material. In the case of the feet-shuffling trick, the two materials are carpeting and your feet. In the case of a car that consistently zaps you after driving it, the materials are typically your clothes and the car seat, which rub together while driving.
What Creates Static in Your Car?
If your clothing and the car seat exchange enough electrons and one side of the equation builds up static electricity, it can discharge when you touch the car door or handle. This phenomenon is more common during periods of dry weather, as static electricity can naturally discharge into moist air, but dry air leaves it nowhere to go. Certain fabrics and some types of seat coverings are more likely than others to generate static electricity. In addition to zapping you when you get in or out of a car, this type of static electricity discharge also presents a genuine, if extremely unlikely, safety concern every time you fill up your car. There is a kernel of truth in the old urban legend about static electricity igniting gas fumes. There are three ways to prevent static shock when getting in or out of a car. Two of these involve preventing static from building up, and the third is a way to discharge any static electricity buildup safely without a painful zap.
Use Antistatic Spray
One way to prevent static electricity from building up in your clothes while driving or when you slide across the seat to exit the vehicle is to spray the seats with an antistatic product. This may or may not be safe for your seats, depending on the material the seat coverings are made of and the makeup of the spray you choose. Find a compatible product and test it on a small, discreet area first. Antistatic sprays create a barrier between the surface of the seat and your clothes. Since static electricity only builds up when electrons pass between two materials and create an imbalance, the thin coating of antistatic spray prevents a charge from building up. Since there’s no charge, you never get zapped.
Install a Static Strap
Another way people deal with this issue is to install a static strap. These products are straps that bolt to the frame or some metal component of your vehicle’s undercarriage. When properly installed, the strap hangs down and contacts the ground beneath the vehicle. The main drawback of static straps is that installing one results in a clearly visible strip of material hanging down from the bottom of your vehicle, which some people find undesirable.
Buy an Antistatic Keychain
Another way to prevent your car from zapping you is to buy an antistatic keychain. These devices provide a safe, painless way to discharge static buildup in your clothes before you touch the door to get out. They typically include a display or light that flashes when static electricity is discharged through it. Other ways to deal with this problem are to first touch the car with your knuckles, which are typically less sensitive than your fingertips or use your elbow or shoulder to close the door.
The Shocking Dangers of Automotive Electrical Systems
The other way a car can zap you occurs when you’re poking around under the hood, and you come into contact with the high voltage passing through the ignition system. While the battery in a car is low voltage and unlikely to shock you under normal circumstances, voltage is stepped up to operate the ignition system.
Stay Away From Ignition Systems
Ignition systems require higher voltages because air/fuel mixtures are ignited inside internal combustion engines. This process relies on a spark jumping across an air gap between two electrodes built into a small component that is inserted into each combustion chamber. These components are called spark plugs because they are literally plugs that have two electrodes across which a spark jumps.
Avoid Distributors in Older Vehicles
In older engines that use distributors, the voltages involved are high and capable of zapping you if you touch the wrong thing, but they usually aren’t dangerous. The higher voltages involved in distributor-less ignition systems are more likely to cause injury, but it’s a good idea to avoid being shocked by either type of system.
Malfunctioning Components
Most ignition system shocks result from a malfunctioning component, such as a spark plug wire that has frayed due to age or proximity to a sharp object or hot surface. This type of malfunction often leads to an engine that doesn’t run well, as the wire shorts out and delivers its charge straight to the ground rather than to its spark plug. If you insert yourself into the equation, you’re likely to get shocked. The best way to avoid being shocked by an ignition system is to be careful around the ignition components whenever the engine is running and replace any worn or malfunctioning components. Hybrid and electric vehicles typically use higher voltage electrical systems than conventional cars and trucks. While it is possible to be shocked by one of those systems, they typically have high voltage wires that are marked carefully to help you avoid them.
