Class 12 Automotive Chapter 5 Auto Electrical System

Class 12 Automotive Chapter 5 Auto Electrical System Solutions English Medium As Per AHSEC New Syllabus to each chapter is provided in the list so that you can easily browse through different chapters Class 12 Automotive Chapter 5 Auto Electrical System Question Answer and select need one. Class 12 Automotive Chapter 5 Auto Electrical System Notes Download PDF. AHSEC Class 12 Elective Automotive Question Answer English Medium.

Class 12 Automotive Chapter 5 Auto Electrical System

Also, you can read the NCERT book online in these sections Solutions by Expert Teachers as per Central Board of Secondary Education (CBSE) Book guidelines. AHSEC Class 12 Elective Automotive Textual Solutions are part of All Subject Solutions. Here we have given AHSEC Class 12 Automotive Textbook Solutions English Medium for All Chapters, You can practice these here.

Auto Electrical System

Chapter: 5

SESSION 1: AUTOMOTIVE ELECTRICAL AND ELECTRONICS SYMBOL

Check Your Progress

A. Fill in the blanks:

1. The symbol for an electrical wire represents the _____________. 

Ans: Electrical wire.

2. Resistor reduces the flow of _____________ in an electrical circuit. 

Ans: Current.

3. Neoprene rubber is often used as insulation for cables due to its resistance to ___________, oil, and heat. 

Ans: Heat.

4. High-tension (HT) cables are used to connect the _____________ to the spark plugs. 

Ans: Ignition coil.

5. The purpose of a wiring harness is to simplify connections and prevent damage from ____________ objects.

Ans: Metal.

B. Multiple Choice Questions:

1. What is the purpose of using automotive electrical symbols? 

(a) To confuse mechanics. 

(b) To simplify circuit diagrams.

(c) To increase voltage.

(d) To generate light.

Ans: (b) To simplify circuit diagrams.

2. Which type of switch disconnects the current when open? 

(a) SPST Toggle Switch.

(b) Pushbutton Switch (N.O). 

(c) SPDT Relay. 

(d) Jumper.

Ans: (a) SPST Toggle Switch.

3. What does a resistor do in an electrical circuit? 

(a) Increases voltage. 

(b) Reduces current flow. 

(c) Acts as a switch. 

(d) Generates light. 

Ans: (b) Reduces current flow. 

4. Which cable is used for the battery circuit? 

(a) Black. 

(b) Green. 

(c) Yellow. 

(d) Brown. 

Ans: (d) Brown.

5. What is the primary purpose of a wiring harness in automobiles? 

(a) To confuse mechanics. 

(b) To increase voltage. 

(c) To simplify connections. 

(d) To generate heat.

Ans: (c) To simplify connections.

6. Which cable is used for the headlamp circuits? 

(a) White. 

(b) Blue. 

(c) Red. 

(d) Black.

Ans: (b) Blue. 

C. Answer the following questions:

1. Draw a neat diagram of following items in symbolic form. 

(a) Fuse.

Ans: —[ ∎ ]—

(A simple rectangle/box in the middle of a line, representing a fuse element that breaks if current is too high.)

(b) Relay.

Ans:  

(A relay consists of a coil and a switch that it controls. The coil symbol and movable switch contact are shown separately.)

(A relay consists of a coil and a switch that it controls. The coil symbol and movable switch contact are shown separately.)

(c) Transistor.

Ans: There are three main types; here is NPN transistor (most common):

(C = Collector, B = Base, E = Emitter. Arrow points out for NPN, in for PNP.)

(d) LED.

Ans: 

(A diode symbol with two outward arrows showing light emission.)

(e) Ground.

Ans: ───

        ──

        ─

(A set of three decreasing horizontal lines stacked vertically, pointing downward.)

2. Write various specifications of Automobile cables.

Ans: Various kinds of cables are employed in the wiring system of present-day automobiles. While selecting the cable size, the voltage drop is kept in mind. Generally, the voltage drops permitted for a particular length of cable under its full current loading capacity is of the order of 10%.

The cables used in automobiles are of the stranded type instead of the single-conductor type. The stranded cables are more flexible than the single one but they are not easily soldered. The size of the cable is designated by the number of

strands and the diameter of each wire used. For instance, a cable having 37 strands of wire, each of 0.875 mm diameter, is designated as a 37/0.875 cable.

3. What do you understand by cable color codes? Classify the Automobile cables. 

Ans: In order to quickly identify and also to simplify the wiring system, the cables are coloured. In addition, colour lines or threads are also used around the cables, which provide a very wide choice of colour combinations. The seven colour code system is the general one and involves brown, yellow, red, white, green, blue and black colours.

(i) Brown Cables: Brown cables are used for the battery circuit. It is used from the cranking motor switch to the ammeter, to the radio receiver, to the electric clock, to the inspection sockets and to the battery auxiliary fuse.

(ii) Yellow Cables: These are used for the generator circuits. The cable is used from the generator terminal to the corresponding control-box terminal and to the ignition warning light.

(iii) White Cables: These cables are used for the ignition circuits and also for other circuits which do not require fuses and are operated through the ignition switch, such as the electric fuel pump, motor starter, solenoid switch etc.

(iv) Green Cables: These cables are used for all the auxiliary circuits which are fed through the ignition switch but are protected by the fuses. Examples of these circuits are the brake stop lamps, the fuel gauge, the windscreen wipers, the direction indicators, etc.

(v) Blue Cables: These cables are used for the headlamp circuits. These cables are used for the side and tail lamp circuits. It is also used for fog lamps, panel lights and other lamps which are only used when the side lamps are in operation.

(vi) Black Cables: These cables are used for the earth circuits.

4. What is Wiring Harness? How does it affect the electrical connections in Automobile?

Ans: The electrical system of present-day cars is quite complex. Connecting each electrical component individually is a tedious and costly affair. With the adoption of the wiring harness method, it has become quite simple to connect the various electrical components. It has also resulted in space saving and safeguarding of the individual cables from metal objects.

The harness consists of bunches of cables leading to the various components to be connected. Each bunch is bound together with a PVC tape, leaving sufficient lengths of individual cables protruding at each end for making the necessary electrical connections easily.

It may be noted that there is a typical drawback to this system. If one of the cables fails, it necessitates the harness to be cut for rectification. However, the present-day cables have got good mechanical strength as well as insulation properties.

SESSION 2: ELECTRICAL TEST EQUIPMENT’S

Check Your Progress

A. Fill in the blanks:

1. One of the simplest types of test equipment is the _______________ wire. 

Ans: Jumper.

2. A test light is limited in that it does not display the ____________ at the point of the circuit being tested. 

Ans: Voltage.

3. Digital multimeters (DMMs) are preferred for testing computer circuits due to their high input resistance, which reduces the risk of ___________ to components. 

Ans: Damage.

4. An oscilloscope displays voltage traces on a screen, representing voltage variations over ____________. 

Ans: Time.

B. Multiple Choice Questions: 

1. What is the primary purpose of using jumper wires in electrical testing? 

(a) To measure resistance.

(b) To diagnose voltage drops.

(c) To provide a ground for testing.

(d) To bypass load components.

Ans: (d) To bypass load components.

2. Which tool is used to “look” for electrical power in a circuit? 

(a) Voltmeter.

(b) Ammeter.

(c) Logic probe.

(d) Ohmmeter.

Ans: (c) Logic probe.

3. Which type of multimeter is recommended for testing computer-controlled circuits due to its high input resistance? 

(a) Analog multimeter.

(b) Digital multimeter (DMM).

(c) Ohmmeter.

(d) Logic probe.

Ans: (b) Digital multimeter (DMM).

4. What is the purpose of a logic probe in electrical testing? 

(a) Measure voltage drops.

(b) Test diodes.

(c) Measure frequency.

(d) Test computer-controlled circuits.

Ans:( d) Test computer-controlled circuits.

5. In a circuit, the sum of voltage drops around the circuit is equal to: 

(a) Zero.

(b) The source voltage.

(c) Infinity.

(d) Half of the source voltage.

Ans: (b) The source voltage.

SESSION 3: BATTERY AND ITS MAINTENANCE

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SESSION 4: CHECKING OF ELECTRICAL CONNECTIONS OF LIGHTING SYSTEM IN A VEHICLE

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SESSION 5: APPLICATIONS AND REPLACEMENT OF FUSES

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SESSION 6: CIRCUIT DIAGRAM OF CHARGING SYSTEM OF AUTOMOBILE AND CHECKING OF CHARGING SYSTEM

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SESSION 7: CIRCUIT DIAGRAM OF STARTING SYSTEM OF AUTOMOBILE AND CHECKING OF STARTER CIRCUIT

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SESSION 8: CIRCUIT DIAGRAM OF IGNITION SYSTEM AND CHECKING OF IGNITION CIRCUIT

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SESSION 9: MAINTENANCE AND SERVICING OF MAJOR ELECTRICAL ACCESSORIES

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SESSION 10: INTRODUCTION TO CLIMATE CONTROL SYSTEM HEATING VENTILATION AND AIR CONDITIONING IN A VEHICLE

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