Brake Systems: Inspection and Evaluation

Hydraulic Brake System Components

• Master Cylinder Inspection: Evaluating the master cylinder for leaks, proper fluid level, and diaphragm condition. Understand the function of primary and secondary pistons, and how to identify internal bypass.
• Brake Lines and Hoses: Identifying types of brake lines (steel, copper, flexible hoses). Inspection includes checking for corrosion, kinks, cracks, bulges, and proper routing. Knowledge of DOT standards for brake hoses is crucial.
• Calipers and Wheel Cylinders: Identifying fixed and floating calipers. Inspection involves checking for leaks, piston movement, boot condition, and proper mounting. Understand the function of bleed screws and their role in brake bleeding.
• Brake Pads and Shoes: Measuring brake pad/shoe thickness using precision tools. Identifying different types of friction materials (organic, semi-metallic, ceramic) and their characteristics. Recognizing signs of glazing, uneven wear, and contamination.
• Brake Rotors and Drums: Measuring rotor thickness and runout using a micrometer and dial indicator. Inspecting for cracks, scoring, heat spots, and warping. Understanding minimum rotor thickness specifications. Drum inspection includes checking for cracks, scoring, and out-of-roundness.

Anti-Lock Brake Systems (ABS)

• ABS Components: Identifying ABS control modules, wheel speed sensors, hydraulic modulator units, and warning lights. Understanding the function of each component in the ABS system.
• Wheel Speed Sensors: Inspecting wheel speed sensors for damage, proper mounting, and wiring integrity. Understanding how wheel speed sensors generate signals (magnetic reluctance, Hall effect).
• Hydraulic Modulator Unit: Identifying the location and function of the hydraulic modulator unit. Understanding how the modulator controls brake pressure to prevent wheel lockup.
• ABS Diagnostics: Recognizing ABS warning light patterns and their potential causes. Using scan tools to retrieve ABS diagnostic trouble codes (DTCs). Understanding basic ABS troubleshooting procedures.

Parking Brake Systems

• Types of Parking Brakes: Identifying cable-operated, electric, and integrated parking brake systems. Understanding the operating principles of each type.
• Cable Inspection: Inspecting parking brake cables for fraying, corrosion, and proper adjustment. Understanding how to adjust cable tension.
• Electric Parking Brakes: Understanding the operation of electric parking brake actuators and control modules. Using scan tools to diagnose electric parking brake faults.
• Parking Brake Performance: Evaluating parking brake holding ability on a slope. Understanding parking brake performance standards.

Steering and Suspension Systems: Inspection and Analysis

Steering System Components

• Steering Linkage: Inspecting tie rod ends, ball joints, and steering rack bushings for wear and play. Understanding the function of each component in the steering linkage.
• Power Steering System: Checking power steering fluid level and condition. Inspecting power steering hoses for leaks and damage. Understanding power steering pump operation.
• Steering Gear/Rack: Inspecting steering gear/rack for leaks, excessive play, and proper mounting. Understanding the operation of different types of steering gears (recirculating ball, rack and pinion).
• Electronic Power Steering (EPS): Understanding the components and operation of EPS systems. Diagnosing EPS faults using scan tools.

Suspension System Components

• Springs: Identifying different types of springs (coil, leaf, torsion bar). Inspecting springs for cracks, sagging, and damage.
• Shock Absorbers and Struts: Inspecting shock absorbers and struts for leaks, damage, and proper damping. Understanding the function of rebound and compression damping.
• Control Arms and Bushings: Inspecting control arms and bushings for wear, damage, and play. Understanding the function of upper and lower control arms.
• Wheel Bearings: Inspecting wheel bearings for play and noise. Understanding different types of wheel bearings (ball, roller, tapered roller).

Suspension Geometry

• Camber: Understanding camber angle and its effect on tire wear and handling. Measuring camber using specialized tools.
• Caster: Understanding caster angle and its effect on steering stability. Measuring caster using specialized tools.
• Toe: Understanding toe-in and toe-out and their effect on tire wear and handling. Measuring toe using specialized tools.
• Ride Height: Measuring ride height and comparing it to manufacturer specifications. Understanding the effect of ride height on suspension geometry.

Tire and Wheel Assembly: Inspection and Standards

Tire Inspection

• Tire Tread Depth: Measuring tire tread depth using a tread depth gauge. Understanding minimum tread depth requirements.
• Tire Wear Patterns: Identifying different tire wear patterns (cupping, feathering, edge wear, center wear) and their potential causes.
• Tire Sidewall Inspection: Inspecting tire sidewalls for cuts, bulges, abrasions, and weather checking. Understanding tire load and speed ratings.
• Tire Pressure: Checking tire pressure using a calibrated gauge. Understanding the importance of maintaining proper tire pressure.

Wheel Inspection

• Wheel Runout: Measuring wheel runout using a dial indicator. Understanding the effect of wheel runout on vehicle vibration.
• Wheel Damage: Inspecting wheels for cracks, bends, and corrosion. Understanding the importance of using properly rated wheels.
• Wheel Fasteners: Inspecting wheel studs and nuts for damage and proper torque. Understanding proper wheel tightening procedures.

Tire and Wheel Assembly Balance

• Static Balance: Understanding static balance and its effect on vertical wheel movement.
• Dynamic Balance: Understanding dynamic balance and its effect on lateral wheel movement.
• Balancing Equipment: Identifying and using different types of wheel balancing equipment.

Lighting and Electrical Systems: Essential Safety Checks

Exterior Lighting

• Headlights: Inspecting headlight alignment and function. Identifying different types of headlight bulbs (halogen, LED, HID). Understanding headlight aiming procedures.
• Taillights, Brake Lights, and Turn Signals: Inspecting taillights, brake lights, and turn signals for proper function and lens condition. Understanding lighting requirements.
• Marker Lights and Reflectors: Inspecting marker lights and reflectors for proper placement and visibility.

Electrical System

• Battery: Inspecting battery terminals for corrosion and damage. Testing battery voltage and capacity.
• Wiring: Inspecting wiring harnesses for damage, corrosion, and proper routing.
• Fuses and Circuit Breakers: Inspecting fuses and circuit breakers for proper rating and function.

On-Board Diagnostics (OBD)

• OBD II System: Understanding the function of the OBD II system and its role in monitoring vehicle emissions.
• Diagnostic Trouble Codes (DTCs): Retrieving and interpreting diagnostic trouble codes using a scan tool.
• Emissions Readiness Monitors: Understanding emissions readiness monitors and their function in determining vehicle readiness for emissions testing.

Body and Structural Integrity: Assessing Vehicle Condition

Structural Components

• Frame Inspection: Inspecting the vehicle frame for rust, cracks, bends, and collision damage. Understanding different types of frame construction (full frame, unibody).
• Unibody Inspection: Inspecting unibody structures for rust, cracks, and evidence of repairs. Understanding the importance of structural integrity in unibody vehicles.
• Welds and Seams: Inspecting welds and seams for proper penetration and corrosion.

Body Panels and Components

• Body Panel Inspection: Inspecting body panels for rust, dents, and collision damage.
• Glass Inspection: Inspecting windshields, windows, and mirrors for cracks, chips, and other damage.
• Bumpers: Inspecting bumpers for damage and proper mounting.

Safety Equipment

• Seat Belts: Inspecting seat belts for proper function and condition.
• Airbags: Inspecting airbags for proper deployment indicators and tampering.
• Mirrors: Ensuring all required mirrors are present, properly mounted, and provide adequate visibility.