Hot-wiring

Hot-wiring is the process of bypassing an automobile's ignition interlock and thus starting it without the key. A legitimate vehicle owner who has lost their vehicle key may implement this process.

Hot-wiring generally involves connecting the two wires which complete the circuit when the key is in the "on" position (turning on the fuel pump and other necessary components), then touching the 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 electronic chip or transponder verification.

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.

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