Basic electrical circuits of a car
1. Wiring diagram
* Shows the location and connections of all electrical components in the vehicle.
* Provides a list of all fuses, relays and harnesses.
2. Diagram of electronic control units (ECU)
* Shows the location and connections of all the computers (ECUs) that control the various vehicle systems.
* Provides insight into data flow and signals between ECUs.
3. Ignition system diagram
* Shows the location and connections of all ignition system components, including the ignition switch, ignition coils, and spark plugs.
4. Launch system diagram
* Shows the location and connections of all starting system components, including the starter, battery, and starter solenoid.
5. Charging system diagram
* Shows the location and connections of all charging system components, including the alternator, voltage regulator and battery.
6. Lighting system diagram
* Shows the location and connections of all lighting system components, including headlights, taillights and turn signals.
7. Security system diagram
* Shows the location and connection of all security system components, including sensors, control unit and alarm.
8. Comfort system diagram
* Shows the location and connection of all comfort system components, including the audio system, air conditioning and power windows.
9. Engine control system diagram
* Shows the location and connections of all engine management system components, including sensors, ECUs and actuators.
10. Transmission system diagram
* Shows the location and connection of all components of the transmission system, including the gearbox, clutch and drive shaft.
Where to find wiring diagrams
*In the vehicle manual
* At a dealer or car service center
*On the Internet (e.g. car manufacturers’ websites)