It consists mostly of the ignition switch, ignition coil, spark plugs, and distributor. When the key is inserted into the assembly and turned to the "start" position, the switch permits current to flow from the battery to the starter, allowing the engine to start. Once the engine is running, the switch moves out of the way so that voltage cannot continue to flow to the starter.
The switch can be found inside most vehicles on the floor behind the seat next to the brake pedal. It has three positions: off, lock, and start. The switch is held in the "off" position by a spring. You must press the button to set it to the "lock" or "start" position. If you leave this area of responsibility to chance, you may find yourself stranded with no means of starting your car!
The key word here is "most". Some cars have multiple ignition switches located elsewhere on the floorboard or under the dashboard. These items will be described separately below.
As for other components, they're part of the standard equipment on most vehicles. Spark plugs fire up the engines, and distributors distribute the electric signal from the coil to the correct cylinder at each firing pulse. They're usually housed in the vehicle's distributor cap or head, which is attached to the end of the engine block.
The ignition system consists of the following major components: a battery, an ignition switch, a coil, contact points, a condenser, a distributor, spark plugs, and wires. The battery provides power to run all the electrical components in your car including the radio, lights, and heater. The key part of the ignition system is the coil which produces a high-voltage current when activated by the primary coil of the distributor. This current passes through the secondary coil of the distributor, which closes the circuit that powers the front lamps and backlights. The remaining components are used to deliver this current to the various parts of the engine at the correct time.
Distributors were first introduced by GM in 1955 for their overhead camshaft engines. Prior to this time, distributors simply passed the current from the coil to the cylinders as required. Today, most ignition systems include a distributor as well as a separate unit called a "distribuator" which operates like the original distributor but uses semiconductor switches instead of magnetic devices. The distribuator allows for more efficient operation of the engine and reduces noise and vibration caused by the magnetic pickup produced by previous designs. A third type of distributor called a "cam-fired" distributor has become popular again on performance vehicles built since 1995. These units distribute power directly from the camshaft without the help of a distributor or bypass valve.
A storage battery, an induction coil, a mechanism to create scheduled high-voltage discharges from the induction coil, a distributor, and a set of spark plugs are the main components of the ignition system. The engine's firing order is determined by a camshaft or crankshaft which has lobes that push against the distributor to direct fuel and air into specific cylinders at the right time.
Induction coils are the key components in an electrical ignition system. They transform low voltage, high current battery power into several thousand volts for use by the other components of the system. An induction coil consists of two layers of metal foil with a magnetic core between them. The number and size of the cores determine how much voltage it can produce. Coils can be made out of many different materials including aluminum, iron, and steel. Each type of material has its advantages and disadvantages. For example, aluminum coils are lighter than iron ones but they cannot carry as much current. A distributor distributes the electric signal from the coil to all of the spark plugs at once. It does this by having some of the contacts on its rotor switch off the circuit when needed. This allows each plug to receive a spark every other rotation of the rotor. The term "distributor" comes from the fact that it spreads out the energy evenly across all of the cylinders.
Cylinder for the Ignition Lock. To start a car, the ignition lock cylinder is a mechanical component into which the ignition key is put. It's installed within the ignition switch, which is the electrical component that locks the ignition and "reads" the anti-theft coding in the key to allow the car to start. Keys that have been worn might cause damage to the "wafer" tumblers or pins within...these keys are not valid for use with this system.
The ignition lock cylinder contains two sets of holes that match up with those on the key blade. When the key is inserted into the ignition, the matching sets of holes activate the locking mechanism inside the ignition lock cylinder. This prevents anyone else from starting the car unless they have access to the ignition key.
The term "ignition lock" refers to the entire unit consisting of the ignition switch and the ignition lock cylinder. If the ignition lock cylinder is missing, then the system is called "unlocked". If the ignition switch is removed from the vehicle electrical system, then the ability to start the car is also lost. The term "ignition lock button" is used to refer to the part of the ignition lock cylinder that is pressed to engage the lock mechanism.
This device keeps the key fob or handkerchief code out of reach of children who may find it tempting to turn the key in the ignition. They can't do so without an adult present who knows the code.
The battery powers the Ignition Switch, and the connection to the battery is on the battery side of the starting solenoid/relay. The ignition switch is usually situated just behind the key cylinder (where you insert your key). This might be in the steering column or the dashboard. When you turn the key in the ignition, it opens both the starter relay and the switch that connects the battery to the ignition coil. The magnetic field created by the ignition coil causes the starter relay to close, which sends a signal to the starter motor to start the engine.
If you take your car out of gear but leave the key in the "on" position, the battery will still power the ignition switch, but there will be no voltage reaching the other parts of the electrical system. The switch itself is normally done with a silicon diode, so there would be no flow of current through it. However, if there is any voltage present on the battery, this diode does not prevent it from being passed on to the rest of the electrical system when the switch is closed by turning the key to the "ignition" position.
This means that if you have your car parked in the driveway and the battery is dead, but the lights are still on, there's still enough electricity flowing through the wiring to the switches to keep them powered up. However, if you go inside and shut the door, the circuit is broken and the lights will eventually come off.