Engine Management Issues

• Check Engine Light: Triggered by a variety of issues related to engine performance.
• Misfires: Can be caused by faulty spark plugs, ignition coils, or fuel injectors.
• Faulty Oxygen (O2) Sensor: Affects fuel mixture and emissions control.
• Mass Air Flow (MAF) Sensor Issues: Improper air-to-fuel ratio can cause rough idling or poor acceleration.
• Knock Sensor Failure: Detects engine knocking/pinging, which can lead to engine damage if not addressed.

    Transmission Problems

• Transmission Control Module (TCM) Errors: Can cause shifting issues, delayed gear engagement, or limp mode.
• Gearbox Sensor Faults: Problems with shift solenoids or clutch engagement can affect transmission performance.
• Automatic Transmission Slipping: Caused by worn transmission components or electronic control issues.

   ABS and Brake System Issues

• ABS (Anti-lock Braking System) Fault: Faulty wheel speed sensors, ABS module, or pump can cause the ABS warning light to turn on.
• Brake Pressure Sensor Malfunctions: Affects the vehicle's brake pressure monitoring and can reduce braking efficiency.
• Faulty Brake Light Switch: Can cause issues with brake lights, cruise control, or automatic gear shifting.

   Airbag and SRS (Supplemental Restraint System) Faults

• Airbag Warning Light: May indicate problems with the airbag sensors, wiring, or the control module.
• Seat Belt Pretensioner Issues: Faulty sensors or circuits can prevent airbag deployment.
• SRS Module Failure: Affects the operation of airbags, requiring diagnostic scanning to reset or repair.

   Emission Control System Faults

• Catalytic Converter Problems: Can trigger fault codes related to emissions or reduced engine power.
• EGR (Exhaust Gas Recirculation) Valve Failure: Can cause rough idling, engine misfires, and increased emissions.
• Evaporative Emission Control (EVAP) System Leak: Can trigger fuel vapor leaks or cause the check engine light to illuminate.

   Fuel System Faults

• Fuel Pressure Sensor Faults: Incorrect readings can lead to poor fuel economy or power loss.
• Fuel Pump Malfunction: Causes starting issues or stalling due to fuel supply problems.
• Faulty Fuel Injectors: Poor fuel delivery can cause misfires, engine hesitation, or rough idling.

    Cooling System Issues

• Coolant Temperature Sensor Failure: Can cause overheating, poor fuel efficiency, or incorrect fan operation.
• Thermostat Malfunction: Can cause the engine to overheat or fail to reach proper operating temperature.
• Radiator Fan Control Faults: The fan may fail to engage properly, causing overheating in heavy traffic or hot conditions.

   Electrical and Sensor Issues

• Battery Management System Errors: Problems with battery charge level monitoring or alternator performance.
• Faulty Throttle Position Sensor (TPS): Can cause rough idling, engine surging, or lack of power.
• Crankshaft/Camshaft Position Sensor Failure: Causes starting issues, stalling, or misfires.

   Steering and Suspension Faults

• Electronic Power Steering (EPS) Faults: Can lead to loss of power steering assistance or warning lights.
• Suspension Height Sensor Problems: Common in vehicles with air suspension, leading to incorrect ride height.
• Steering Angle Sensor Faults: Affects stability control, ABS, and electronic steering systems.

    Exhaust and Turbocharger Problems

• Exhaust Gas Temperature Sensor Fault: Can cause turbocharger issues or excessive exhaust emissions.
• Turbocharger Boost Pressure Issues: Over-boost or under-boost conditions may occur due to faulty wastegates, boost sensors, or actuators.

    Body Control System Faults

• Central Locking/Key Fob Malfunction: Problems with remote locking, unlocking, or starting.
• Window and Door Control Issues: Electrical faults in window regulators or door locks.
• Lighting System Faults: Headlight or tail light failure due to control module issues.

    DPF (Diesel Particulate Filter) Issues (For Diesel Cars)

• DPF Blockage: Results in poor engine performance and may require regeneration.
• DPF Sensor Malfunction: A faulty sensor may trigger the warning light even if the DPF is working correctly.

    HVAC (Heating, Ventilation, Air Conditioning) System Faults

• Blower Motor Failure: Can cause issues with cabin airflow.
• AC Compressor or Sensor Issues: Leads to air conditioning malfunction or lack of cooling.
• Climate Control Module Faults: Affects temperature regulation and defrost functions.

 Immobilizer and Security System Faults

• Immobilizer Errors: Can prevent the vehicle from starting due to key recognition issues.
• Alarm System Faults: May prevent the vehicle from locking/unlocking properly.  

Parking Sensors and Camera System Faults

• Parking Sensor Malfunctions: Caused by faulty sensors or wiring, making the parking assist system unreliable.
• Backup Camera Issues: Display or sensor failures can affect visibility and safety during reversing.

Using a diagnostic machine is essential in modern cars since most of these faults involve the car's electronics or complex systems that require scanning and reading error codes for proper identification.