University of Technical Education Ho Chi Minh City INTRODUCTION TO AUTOMOTIVE ELECTRICAL AND ELECTRONIC SYSTEMS Le Thanh Phuc Faculty of Automotive Engineering Email: thanhphucckd@gmail.com Automotive electrical and electronic systems Main systems Starting Charging Ignition Lighting and signal Information Engine control Automotive control Air conditioning Accessories Components of a circuit Series Circuits Series Circuits •A series circuit has only one path for current That means current is the same through every part of the circuit • If any part of the circuit is broken or disconnected, the whole circuit will stop working •No current is present in a series circuit unless there is continuity through the entire circuit •You can use Ohm's Law to predict the behavior of electricity in a circuit Voltage Drops in a Series Circuits Parallel Circuits Parallel Circuits A parallel circuit has these key features: • Total current equals the sum of the branch currents • Resistance of each branch determines the current through each branch • If the branch resistances are the same, branch currents will be the same • If the branch resistances are different, the current in each branch will be different • The voltage drop across each load resistance is the same This is because the source voltage is applied equally to each branch • The equivalent resistance of the circuit is less than the smallest branch resistance Circuit Connection Electrical Symbols Wiring Diagram Inductors A Simple Electromagnet A simple electromagnet can be made from a length of wire, a battery, and a nail Depending on the size of the battery, this circuit might require some added resistance to keep excess current from burning the wire Voltage Generated by Induction When a current flowing through a coil is cut off, the collapsing magnetic field generates a voltage spike Ignition Coil An ignition coil takes advantage of the collapsing magnetic field to generate a high voltage pulse for the spark plugs Relay Relays are used throughout the automobile Relays which come in assorted sizes, ratings, and applications, are used as remote control switches Relay A relay uses an electromagnetic coil to move a set of contacts Relay Capacitor Capacitors have the ability to absorb and store an electrical charge and then release it into the circuit Noise suppression— Noise in an audio system is often caused by AC electrical voltage riding on top of the DC voltage supplying power to a radio or tape player Spike suppression— A capacitor can absorb voltage spikes in a circuit Timers— A resistor put in series with a capacitor can keep current flowing in a circuit for a specified amount of time after power from the source has been removed Diode Diodes block current flow in one direction and pass current in the opposite direction This is accomplished by joining a layer of P type material and a layer of N type material during manufacturing Diode Rectification— Since a diode will allow current to flow in one direction and not the other, it can be used to turn alternating current into direct current Diode Application of diodes on alternators Transistor A transistor can be used as an amplifier to control electric motor speed such as AC blower motors, or as solid state switches to control actuators such as fuel injectors Transistor [...]... magnetic field to generate a high voltage pulse for the spark plugs Relay Relays are used throughout the automobile Relays which come in assorted sizes, ratings, and applications, are used as remote control switches Relay A relay uses an electromagnetic coil to move a set of contacts Relay Capacitor Capacitors have the ability to absorb and store an electrical charge and then release it into the circuit... Control and Ground Control Circuits Electrical Symbols Wiring Diagram Inductors A Simple Electromagnet A simple electromagnet can be made from a length of wire, a battery, and a nail Depending on the size of the battery, this circuit might require some added resistance to keep excess current from burning the wire Voltage Generated by Induction When a current flowing through a coil is cut off, the collapsing... direction and pass current in the opposite direction This is accomplished by joining a layer of P type material and a layer of N type material during manufacturing Diode Rectification— Since a diode will allow current to flow in one direction and not the other, it can be used to turn alternating current into direct current Diode Application of diodes on alternators Transistor A transistor can be... alternating current into direct current Diode Application of diodes on alternators Transistor A transistor can be used as an amplifier to control electric motor speed such as AC blower motors, or as solid state switches to control actuators such as fuel injectors Transistor ... charge and then release it into the circuit Noise suppression— Noise in an audio system is often caused by AC electrical voltage riding on top of the DC voltage supplying power to a radio or tape player Spike suppression— A capacitor can absorb voltage spikes in a circuit Timers— A resistor put in series with a capacitor can keep current flowing in a circuit for a specified amount of time after power .. .Automotive electrical and electronic systems Main systems Starting Charging Ignition Lighting and signal Information Engine control Automotive control Air conditioning... coil to move a set of contacts Relay Capacitor Capacitors have the ability to absorb and store an electrical charge and then release it into the circuit Noise suppression— Noise in an audio system. .. alternating current into direct current Diode Application of diodes on alternators Transistor A transistor can be used as an amplifier to control electric motor speed such as AC blower motors, or as solid