Lesson Note on Suspension System—Fault Finding in Suspension System: Faulty Areas for SS2

Class: Senior Secondary School 2 (SS2 / SSS2)
Term: First Term
Week: 10
Age: 16 years
Duration: 45 minutes
Subject: Auto Mechanic Work
Curriculum Theme: Vehicle Systems
Previous Lesson: Suspension System—Hydraulic Suspension System: Removal and Replacement.
Topic: SUSPENSION SYSTEM—FAULT FINDING IN SUSPENSION SYSTEM
Subject Matter: Meaning of SUSPENSION SYSTEM—FAULT FINDING IN SUSPENSION SYSTEM (definition of suspension fault diagnosis), identify faulty areas (leaf spring, coil spring, joints, mountings), fault finding in suspension system (inspection, testing).

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

• Define suspension system fault diagnosis.
• Identify common faulty areas in a suspension system.
• Describe the procedures for fault finding in a suspension system.

Affective Domain:

• Appreciate the importance of proper fault diagnosis in vehicle safety.
• Develop an interest in practical fault-finding techniques.

Psychomotor Domain:

• Demonstrate visual inspection of suspension components.
• Point out specific faulty areas on actual suspension parts.

Social Domain:

• Collaborate with peers to identify potential suspension faults.

Reference Materials

The following resources were used in planning this lesson:

• Senior Secondary Schools Education Curriculum
• State Unified Scheme of Work
• R.B. Heitner, Automotive Mechanics
• https://www.autozone.com/repairinfo/repairguide/repairGuideContent.jsp?pageId=09968002800a7b45
• https://www.youtube.com/watch?v=kR211wBvB5o

Instructional Materials

The teacher will teach this lesson with the aid of:

• Charts showing suspension systems and common faults
• Posters
• Actual leaf spring
• Actual coil spring
• Actual shock absorber
• Various suspension joints (ball joints, tie rod ends)
• Worn bushings
• Basic hand tools

Rationale for the Lesson

Understanding suspension system fault finding is important for pupils to correctly diagnose vehicle problems, which helps ensure vehicle safety and extends the lifespan of suspension components. This knowledge enables pupils to maintain vehicles effectively.

Prerequisite/Previous Knowledge

Pupils should have prior knowledge of the main components and basic functions of a vehicle suspension system.

Lesson Content/Board Summary

SUSPENSION SYSTEM—FAULT FINDING IN SUSPENSION SYSTEM

Meaning of Suspension System Fault Diagnosis

Suspension system fault diagnosis is the process of identifying and determining the cause of problems or malfunctions within a vehicle’s suspension system. This process helps to restore proper handling, ride comfort, and safety.

Common Faulty Areas in a Suspension System

The following are common areas where faults can occur in a suspension system:

• Leaf Springs: Broken leaves, cracked leaves, flattened springs.
• Coil Springs: Broken coils, sagging springs, cracked springs.
• Shock Absorbers/Struts: Leaking fluid, worn seals, bent rods, broken mounts, lack of damping effect.
• Bushings: Worn, cracked, or deteriorated rubber bushings in control arms, sway bars, and spring eyes.
• Ball Joints: Worn or loose ball joints, torn boots allowing dirt ingress.
• Tie Rod Ends: Worn or loose inner or outer tie rod ends.
• Control Arms: Bent or cracked control arms.
• Mountings: Loose or broken mounting bolts, deteriorated rubber mounts.

Fault Finding in Suspension System

Fault finding involves systematic inspection and testing:

1. Visual Inspection

This involves carefully looking at the suspension components for obvious signs of damage or wear.

• Check for broken or cracked springs (leaf or coil).
• Look for fluid leaks around shock absorbers or struts.
• Inspect bushings for cracks, tears, or excessive wear.
• Examine ball joint and tie rod end boots for tears.
• Check for bent or damaged control arms, sway bars, or links.
• Look for loose or missing fasteners and mounts.
• Observe vehicle height and stance for unevenness.

2. Testing Procedures

These tests help confirm suspected faults or identify less obvious issues.

• Bouncing Test: Push down firmly on each corner of the vehicle and release. The vehicle should rebound once or twice and then settle. Excessive bouncing indicates worn shock absorbers.
• Road Test: Drive the vehicle to observe symptoms such as:
  • Excessive body roll during cornering.
  • Nose dive during braking or squat during acceleration.
  • Unusual noises (clunking, squeaking, rattling) over bumps.
  • Poor steering response or wandering.
  • Uneven tire wear patterns.
• Shake Test (on a lift): With the vehicle on a lift, use a pry bar to check for play in ball joints, control arm bushings, and tie rod ends.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Set Induction

Teacher’s Activity: The teacher greets the pupils and briefly reviews the previous lesson on suspension system components. The teacher then introduces the topic: “Suspension System—Fault Finding in Suspension System.”

Pupils’ Activity: Pupils respond to greetings and recall previous knowledge. They listen attentively to the new topic.

Learning Point: Pupils are prepared for the new lesson and connect it to prior knowledge.

Step 2: Meaning of Suspension System Fault Diagnosis

Time: 8 minutes

Teaching Skill: Explanation

Teacher’s Activity: The teacher explains the meaning of suspension system fault diagnosis using simple terms and examples.

Pupils’ Activity: Pupils listen, ask questions for clarification, and take notes.

Learning Point: Pupils understand the definition of suspension system fault diagnosis.

Step 3: Identifying Common Faulty Areas

Time: 10 minutes

Teaching Skill: Demonstration/Identification

Teacher’s Activity: The teacher uses charts, posters, and actual suspension components (leaf spring, coil spring, shock absorber, bushings) to show and explain common faulty areas such as broken springs, leaking shocks, and worn bushings. The teacher guides pupils to identify these areas.

Pupils’ Activity: Pupils observe the charts and components, identify the faulty areas as pointed out by the teacher, and ask questions.

Learning Point: Pupils can identify various common faulty areas in a suspension system.

Step 4: Fault Finding Process—Visual Inspection

Time: 8 minutes

Teaching Skill: Demonstration

Teacher’s Activity: The teacher explains and demonstrates the steps involved in a visual inspection of suspension components, pointing out what to look for (e.g., cracks, leaks, tears, looseness).

Pupils’ Activity: Pupils observe the demonstration and note the key points of visual inspection.

Learning Point: Pupils learn how to conduct a basic visual inspection for suspension faults.

Step 5: Fault Finding Process—Testing Procedures

Time: 8 minutes

Teaching Skill: Explanation

Teacher’s Activity: The teacher explains different testing procedures like the bouncing test and road test, describing what symptoms to look for during each test.

Pupils’ Activity: Pupils listen to the explanations of testing procedures and understand their purpose.

Learning Point: Pupils understand various methods for testing suspension system performance.

Step 6: Practical Identification

Time: 5 minutes

Teaching Skill: Practical Application

Teacher’s Activity: The teacher provides various suspension components (some with simulated faults) and asks pupils to identify and describe potential faults on them.

Pupils’ Activity: Pupils work in groups or individually to examine the components and identify faults.

Learning Point: Pupils apply their knowledge to practically identify faults on suspension parts.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. Define suspension system fault diagnosis.
2. Mention three common faulty areas in a suspension system.
3. Describe two methods of visual inspection for suspension faults.
4. Explain the purpose of a bouncing test in fault finding.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 1 minute

Teaching Skill: Summarization

Teacher’s Activity: The teacher summarizes the main points of the lesson and gives homework: “List five symptoms of a faulty suspension system that a driver might notice.”

Pupils’ Activity: Pupils listen to the summary and copy the homework.

Learning Point: The lesson is reinforced, and pupils have further tasks.

Lesson Keywords

• Suspension System – A system of springs, shock absorbers, and linkages that connects a vehicle to its wheels, allowing relative motion between the two.
• Fault Diagnosis – The process of identifying the cause of a problem or malfunction.
• Leaf Spring – A type of spring used in suspension systems, typically found in heavy vehicles, made of layers of metal strips.
• Coil Spring – A type of spring used in suspension systems, made of a coiled metal rod.
• Shock Absorber – A device that controls unwanted spring motion by converting kinetic energy into thermal energy.
• Bushings – Rubber or polyurethane components used to cushion and reduce vibration between suspension parts.
• Ball Joint – A spherical bearing that connects the control arms to the steering knuckles, allowing for movement in multiple directions.
• Visual Inspection – Checking components by looking at them for signs of wear or damage.
• Bouncing Test – A simple test to check the condition of shock absorbers by pushing down on the vehicle’s corners.

Differentiation

For pupils who struggle, the teacher will provide simplified diagrams and focus on identifying the most common faults using physical components. Advanced pupils will be challenged to research specific diagnostic tools or advanced testing procedures for suspension systems.

Note for teachers using this lesson plan

Ensure that actual suspension components are available for pupils to touch and examine to enhance practical understanding. Emphasize safety precautions when handling vehicle parts and performing inspections. Encourage pupils to ask questions and share their observations.