Hot-wiring is the process of bypassing a motor vehicle's ignition switch and thus starting it without the key. It is often utilized during a vehicle theft. However, a legitimate vehicle owner who has lost their vehicle key or starting a vehicle with inoperable ignition switch (e.g. in run-down old cars) may also implement this process.
Methods
Hot-wiring generally involves connecting the wires which complete the circuit when the key is in the "on" position (turning on the fuel pump and other necessary components), then touching another wire that connects to the starter. The specific method of hot-wiring a vehicle is dependent on the particular vehicle's electrical ignition system. Remote start units access the same wires as conventional ignition methods. Listings of wire colors and locations and ignition system schematics may sometimes be found in Internet databases.
Motorcycles and older cars, which often have a carbureted engine and a single ignition coil and distributor, can be hot-wired from the engine bay. Using standard lock picking to start a vehicle is now usually ineffective, since most cars now use immobilisers or transponder key verification. Conversely, most types of motorcycles are often easier to hot-wire, especially scooters and older naked bikes, which lack advanced security features beyond mechanical locks and conventional ignition switch.
Thieves lacking the basic mechanical skills and knowledge of automotive electrical systems sometimes simply use physical force to bypass the ignition lock, smashing the key mechanism to reveal the rotation switch, which is operated by the key's tumbler.