ASE A7 HVAC Final

Front

A vehicle's air conditioning performance is reduced at low speeds and stop lights, but cools at highway speeds. Which of these is MOST likely the cause of this condition? A low refriderant charge., A defective radiator cooling fan., A normal condition., A faulty compressore clutch relay.

Back

A defective radiator cooling fan.

Front

A frozen spot is noticed in the center of the condenser. Technician A says a frozen spot on a component or connection indicates a restriction in the system. Technician B says this is caused by too much freon. Who is correct?

Back

Technician A only

Front

A technician is diagnosing a vehicle's air conditioning system. The vehicle has good engine performance, but the air conditioner is blowing warm air only. A yellow substance is noticed around the evaporator case drip tube. Technician A says this is coolant leaking from the heater core. Technician B says this is fluorescent dye leaking from the evaporator core. Which technician is MOST likely correct?

Back

Technician B only

Front

Two technicians are discussing electric cooling fans and air conditioning performance. Technician A says electric fans regulate refrigerant temperatures more precisely than belt driven fans do. Technician B says electric cooling fans are controlled by control modules that use temperature and pressure actuated sensors and switches. Who is correct?

Back

Both Technician A and B

Front

Who is correct regarding the clutch relay: Technician A says the clutch relay protects the control head from the clutch circuit's high current. Technician B says open clutch relay windings result in compressor clutch engagement at all times?

Back

Technician A only

Front

All of these are true about an air conditioner's evaporator EXCEPT: It removes humidity from the air., Refrigerant flows from the bottom to the top., Refrigerant enters the evaporator as a liquid., The refrigerant changes from a vapor to a liquid as it receives heat from the cabin air.

Back

The refrigerant changes from a vapor to a liquid as it receives heat from the cabin air.

Front

A blower motor operates only in high speed. Technician A says there could be a short in the motor's power feed. Technician B says it may have a faulty blower motor resistor. Who is correct?

Back

Technician B only

Front

A compressor clutch coil is being tested. There is 12 volts at the connector and the ground is good. The resistance of the coil is 0.00 Ohms. Technician A says the coil has an open in its windings. Technician B says the clutch coil has a short and has failed the resistance test. Who is correct?

Back

Technician B only

Front

The carpet is wet on the passenger's side of a vehicle. Technician A says this may be caused by a leaking heater core. Technician B says this could be caused by a clogged evaporator case drain tube. Who is correct?

Back

Both Technician A and B

Front

An EATC air conditioning system has low fan speed operation during high demand situations, like in direct sunlight. Technician A says this is because something is covering the sun load sensor's photo diode. Technician B says a sun load sensor is a variable resistor and can be tested with an ohmmeter. Who is correct?

Back

Both Technician A and B