Download Question 3 Electrical Components [10marks]

Question 1
Multiple Choice
[5 marks]
Choose the most suitable answer from the given statements and write the letter of your
choice against the number of statement.
Fundamental of Electricity
1. When two materials are rubbed together, __________electricity is produced!
a)
Pulsing
b)
D.C.
c)
A.C.
d)
static
2. The basic SI unit of Power is the:
a)
Joule
b)
Watt
c)
Newton
d)
Horsepower
e)
Horsepower
3. Electrons have a:
a) neutral Charge
b) positive Charge
c) negative Charge
d) variable Charge
4. An electrical transmission line is rated at 330kV, which is the equivalent of:
a) 3300V
b) 330 000V
c) 330V
d) 33 000V
5. For accuracy, the most important preparation for an ohmmeter is:
a) set it to its highest scale
b) zero the meter
c) clean the terminals and check the battery place the meter down flat
Question 2
Electromagnetism
[7 marks]
Electricity and magnetism are closely related. _______A________can be used to produce electricity.
And, ______B__________can be used to produce magnetism.
All ______C______carrying current create a magnetic field. The magnetic field strength is changed by
changing ______D_________, ________E________, ________F__________.
With a straight conductor, the magnetic field surrounds it as a series of circular lines of force. With a
looped (coil) conductor, the lines of force can be _______G_________to make a very strong field.
Trimester 1/2015
AUT312-Electrical/Electronics & Fuel System
Page 1
Question 3
Electrical Components
[10marks]
a) Complete the table below.
[10marks]
Trimester 1/2015
AUT312-Electrical/Electronics & Fuel System
Page 2
Question 4
Automotive Batteries
[5marks]
a. Study the battery construction shown below and identify the numbered parts.
[5marks]
Question 5:
Calculation
[10 Marks]
a) In the diagram below, calculate the following:
i. The total resistance for the above circuit.
[2 marks]
ii. The current through R 1 .
[1/2 mark]
iii. The voltage drop across R 1
[1/2 mark]
iv. The voltage drop across R 4 .
[1/2 mark]
v. The power dissipated in the circuit.
[1/2mark]
b) The resistance and the tolerance value for a resistor with the color code (band 1 to 3) Red,
Orange and Yellow would be.
c) State the three characteristics of series circuit.
Trimester 1/2015
AUT312-Electrical/Electronics & Fuel System
[3 marks]
[3 marks]
Page 3
Question 6
Ignition System
[15 Marks]
a) Name what type of ignition system given in the diagram below.
[1 mark]
b) Briefly discuss the operation of the given Circuit diagram above.
[8 marks]
c) How is the secondary circuit of the system earthed?
[4 marks]
d) How does the secondary current create a spark?
[2 marks]
Question 7
Starting System
[15marks]
a) Draw the wiring diagram of a starting system.
[5marks]
b) Describe the starter motor operation.
[7marks]
c) State the function of the following starter motor components:
Question 8
i. Solenoid
[1mark]
ii. Field winding
[1mark]
iii. Armature
[1mark]
Charging System
[15marks]
a) Draw the wiring diagram of a charging system.
[7marks]
b) Describe the charging system operation.
[3marks]
c) State the function of the following alternator component:
Trimester 1/2015
i.
Voltage Regulator
[1mark]
ii.
Pulley
[1mark]
iii.
Heat sink
[1mark]
iv.
Diodes
[1mark]
v.
Brushes
[1mark]
AUT312-Electrical/Electronics & Fuel System
Page 4
Question 9
Lighting System
[5marks]
a) For the given automotive lights below, state their function and the bulb power rating.
Bulb Power Rating
Function of the light
Reverse Light
Stop Light
Hazard light
Traffic Indicator
Fog Light
[5marks]
Question 10
Fuels and Fuel Supply System
A. Describe the combustion characteristics of the following Air/Fuel ratio:
i.
B.
22:1
ii. 14.7:1
[13marks]
[3marks]
iii. 18:1
Multiple Choice
[10marks]
1. Octane rating of fuel is:
(a) A lead-based, anti-knock additive used in leaded gasoline
(b) A measure of how resistance gasoline is to premature detonation
(c) A violent collision of flame fronts in the cylinder
(d) The spontaneously burning of air/fuel mixture before spark plug is fired
2. The air/fuel ratio necessary for complete combustion is called:
(a) Additive mixture
(b) Emission control
(c) Stoichiometric ratio
(d) Volume to mass ratio
3. Premature detonation or knocking is:
(a) A lead-based, anti-knock additive used in leaded gasoline
(b) A measure of how resistance gasoline is to premature detonation
(c) A violent collision of flame fronts in the cylinder
(d) The spontaneously burning of air/fuel mixture before spark plug is fire
4. Which statement correctly relates to the function of the Electronic Control Unit (ECU)?
(a) ECU is controlled by the injectors
(b) ECU determines precisely, how much fuel to be delivered by the engine sensors
(c) ECU pulses the injector by switching the injector ground circuit ON and OFF
(d) ECU signals the fuel pump to pump just enough fuel to achieve an ideal air/fuel
Trimester 1/2015
AUT312-Electrical/Electronics & Fuel System
Page 5
5. The purpose of the fuel injection system is to:
(a) Allow additional air to bypass the throttle plate during cold start and warm up
conditions
(b) Maintain suitable idle speed to prevent stalling when additional load is placed on the
engine
(c) Precisely inject a metered amount of fuel at the correct time
(d) Spray fuel into the exhaust valve port
6. Which component removes pressure pulsations caused by the fuel pumps or injectors?
(a) Damper
(b) Filter
(c) Rail
(d) Strainer
7. Which of the following is NOT an EFI system sensor?
(a) Air inlet temperature sensor
(b) Engine temperature sensor
(c) Exhaust back pressure sensor
(d) Throttle position sensor
8. Which of the following sensors monitor the oxygen content in the exhaust gas and relay
the information to the ECU?
(a) Airflow sensor
(b) Engine temperature sensor
(c) Exhaust back pressure sensor
(d) Throttle position sensor
9. The best equipment to measure voltage or resistance in an electronic engine
management sensor is:
(a) High impedance digital meter
(b) Test lamp
(c) Jumper wires
(d) Vacuum pump gauge
10. Distributor less ignition system that uses coil to supply voltage to the sparks is called:
(a) Breaker ignition
(b) CB ignition
(c) Direct ignition
(d) Electronic ignition
Trimester 1/2015
AUT312-Electrical/Electronics & Fuel System
Page 6