Ignition switch

An ignition switch or starter switch is a switch in the control system of an internal combustion engined motor vehicle that activates the main electrical systems for the vehicle. Besides providing power to the starter solenoid and the ignition system components (including the engine control unit and ignition coil) it also usually switches on power to many "accessories" (radio, power windows, etc.). The ignition switch usually requires a key be inserted that works a lock built into the switch mechanism. It is frequently combined with the starter switch which activates the starter motor. The ignition locking system may be bypassed by disconnecting the wiring to the switch and manipulating it directly; this is known as hotwiring.

The ignition system is used to ignite the fuel-air mixture in the engine. The starter system is the ignition system, plus the battery, and starter switch, starter solenoid and electric starter motor.

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