If someone, especially a thief, hot-wires a car, they start its engine using a piece of wire rather than the key. A youth was inside the car, attempting to hot-wire it. to start the engine of a vehicle using the wires of the ignition system, instead of a key
start (a car engine) without a key by short-circuiting the ignition system; "The woman who lost the car keys had to hot-wire her van