Automotive Electrical Concepts

Explore automotive voltmeter use, including DC and AC voltage, resistance and ohms testing, proper lead connections, and safe practices with a car battery and household outlet.

Explore how wires act as resistors, how diodes control current, and how fuses, switches, resistance, and voltage drops shape automotive electrical circuits, aided by diode testing with a voltmeter.

Explore how automotive fuses work, from old glass fuses to modern plastic-housed types, learn amp color coding and sizes, and test with a test light to identify blown fuses.

Learn how switches open and close circuits, including electronic types, and how relays use an electromagnet to control large circuits with small control wires.

Explore how an electromagnet creates a magnetic field from an electrical circuit, how turning power on and off magnetizes metal, and how relays use this principle.

Explore how relays let a small control circuit switch a larger automotive circuit, using a magnetic field coil to close contacts and switch power to devices like radiator fans.

Apply Ohm's law to automotive circuits by analyzing resistance, current, and voltage in loads like starters and bulbs, and use fuses to protect circuits.

Demonstrate voltage drop testing in automotive circuits using a live vehicle and a voltmeter to locate where voltage is lost and lights become dim.

Watch a live voltage drop test demonstration to diagnose battery circuit issues, showing corrosion at battery posts, open connections, and how zero-volt drops reveal a good path to the starter.

Explore how a lead acid battery powers cars with six positive and six negative plates separated by an insulator, filled with acid, and recharged by the alternator to 12.6 volts.