Auto Electrical Works Paper 2, WASSCE (SC), 2017

Question 6

 

  • (a) State two causes of each of the following in a motor vehicle:
    (i) horn not honking;
    (ii) poor operation of wiper;
    (iii) malfunctioning washer.
    (b) State:
    (i) two types of fuel gauge;
    (ii) the function of a fuel guage;
    (iii) one symptom of a faulty fuel gauge.
    (c) List three stages of a fault finding in an auxiliary system of a motor vehicle.

 

Observation

   The candidates were expected to copy and complete the table.

  • (a)(i) Causes of motor vehicle horn not honking

    • Relay not working
    • High resistance contact/switch
    • Loose/broken wiring
    • Partial/loose switch contact
    • Torn/broken diaphragm
    • Blown fuse

                                                                                    
    (ii) Causes of poor operation of wiper

    • Loose/broken wiring.
    • Switch not making contact.
    • Worn motor brushes/slip rings connection.
    • Relay timer not working.
    • Blown fuse                                                                  

       (iii) Causes of malfunctioning washer

    • Corrosion in washer motor connection.
    • Loose or broken wiring/fuse.
    • Switch not making contact.
    • Blocked pipes/jets/hose.

                                                                                 
    (b)(i) Types of fuel gauge

    • Magnetic fuel gauge
    • Bimetallic fuel gauge.                                                                                           

         (ii) Fuel gauge indicates the level of fuel contained in a tank.                                
    (iii) Symptoms of a faulty fuel gauge

    • Fluctuating indicator pointer
    • Pointer failure
    • Hanging indicator pointer

    (c) Stages of fault finding in an auxiliary system of a motor vehicle

    • Observe and verify the fault/troubleshooting/diagnosing.
    • Collect further information.
    • Evaluate the evidence.
    • Carry out further tests in a logical sequence.
    • Rectify the fault/finding possible solution.
    • Check the system and all other systems.

    Many candidates did not show familiarity to this question. However, responses to question can be rated average.