Automotive HVAC (Chapter 5)

What is the purpose of checking the engine coolant level during initial vehicle inspection?

• To assess battery health

• To verify tire pressure

• To check the oil level

• To ensure proper engine cooling

What does checking the magnetic clutch operation verify?

• The condenser fan speed

• The drive belt tension

• The coolant level

• The engagement of the A/C compressor

What is indicated by an excessive temperature difference at the inlet and outlet of the condenser?

• A blockage

• Faulty compressor

• Low refrigerant levels

• High ambient temperature

What is the maximum allowable temperature difference at the inlet and outlet of the evaporator?

• 4°C

• 10°C

• 15°C

• 20°C

What is the normal low-side pressure range for R-134a at 25°C?

• 90–100 psi

• 70–80 psi

• 50–60 psi

• 30–40 psi

What does a low high-side pressure indicate?

• High ambient temperature

• Blocked evaporator

• Overcharged refrigerant

• Insufficient refrigerant

What is the purpose of cycle testing in HVAC diagnosis?

• To evaluate system engagement and disengagement

• To check refrigerant levels

• To measure ambient temperature

• To inspect the drive belt

What could cause irregular cycling of the compressor?

• Sensor failure

• Blocked condenser

• Faulty drive belt

• Low refrigerant levels

What should be monitored during cycle testing?

• Compressor clutch

• Battery voltage

• Tire pressure

• Oil levels

What does checking the pollen filter verify?

• Air quality within the vehicle

• Drive belt tension

• Coolant circulation

• Compressor performance