A7 Heating and Air Conditioning


A-7 Heating and Air Conditioning Part 3

Progress:

1. All of the following are true statements concerning in-line filters EXCEPT

2. A customer with an ATC (automatic temperature control) equipped vehicle complains that the car does not get cool enough on hot days. Technician A says that the programmer is the problem. Technician B says that the blend door actuator could be the problem. Who is correct?

3. A customer complains that when accelerating his car with the A/C on, the cold air flow from the dash outlets shifts to the floor. Technician A says that this is caused by a faulty check valve in the vacuum reservoir. Technician B says that this condition is due to a vacuum leak. Who is right?

4. Technician A says "U" DTCs indicate there is nothing wrong with the A/C system. Technician B say when there is a "U" DTC, it should be repaired before any further diagnostics can be performed. Who is correct?

5. The compressor in an A/C system does not run. When a jumper wire is used to connect the battery positive terminal to the power connector, the compressor clutch engages. Technician A says that the clutch coil is defective. Technician B says that the pressure cycling switch could be defective. Who is correct?

6. Which of the following sensors is NOT an NTC thermistor?

7. Observing the data stream while operating a HVAC system on a late model vehicle with Automatic Temperature Control (ATC) the counts for the blend door change when the vehicle is moved outside in the mid day sun. Technician A says that under no circumstances should the counts change on the blend door motor. Technician B says there is an intermittent problem with the blend door actuator that will eventually set a DTC. Who is correct?

8. Technician A says that an ambient temperature sensor provides input for the ATC (Automatic Temperature Control) system. Technician B says that an ambient temperature switch protects the compressor from damage. Who is correct?

9. The floor inside a vehicle is wet and there is a slimy film on the windows. Technician A says that the heater core is leaking. Technician B says that the evaporator case drain plug is clogged. Who is correct?

10. When diagnosing an ATC (Automatic Temperature Control) system, most of the system temperature sensors can be tested for:

11. The A/C compressor cycles rapidly, and air coming from the vents is only slightly cool. Technician A says the problem could be a low refrigerant charge. Technician B says the problem could be a defective thermostatic switch. Who is correct?

12. Technician A says that a special tool is required to disconnect and connect spring lock fittings. Technician B says that new when assembling spring lock fittings, new 0-rings lubricated with clean refrigerant oil should be used. Who is correct?

13. When an A/C system is operating, a clicking or buzzing noise is heard coming from the compressor. Technician A says that this noise means that the system is overcharged. Technician B says that the noise could be due to air in the system. Who is correct?

14. All of the following are true statements about receiver/driers EXCEPT:

15. Technician A says that the A/C system can be charged through the high or low side only when the engine is not running. Technician B says .that the A/C system can be charged though the low slde when the engine is running. Who is correct?

16. All of the following are causes for fan clutch replacement EXCEPT:

17. If a capillary tube were to break at some point between its sensing bulb and the expansion valve, what affect would it have on the valve?

18. A major cause for the depletion of the ozone layer has been attributed to:

19. A compressor clutch will not engage. All of the following could be the cause EXCEPT:

[caption id="attachment_1491" align="aligncenter" width="295"] Click image for larger view
Full Size View[/caption] 20. The cooling fan works on high speed but not on low speed. All of the following are possible causes EXCEPT:

21. The ambient temperature sensor in an ATC (automatic temperature control) system is being tested. Technician A says that, as the sensor resistance changes, the computer reads the change in voltage drop across the sensor. Technician B says that the resistance of the sensor should increase as it is heated. Who is correct?

22. An A/C system retrofit is being discussed by two Technicians. Technician A says that the receiver/drier should be replaced. Technician B says that a high-pressure cutout switch must be added to the system. Who is correct?

23. Technician A says that mineral deposits can restrict air flow through the radiator. Technician B says that internal restrictions in the radiator can be detected from the outside. Who is correct?

[caption id="attachment_1492" align="aligncenter" width="233"] Click image for larger view
Full Size View[/caption] 24. The blower motor works on all speeds except low. Technician A says that this could be caused by an open in circuit 14S between the P/BL and P/0 splice and the motor. Technician B says that this could be caused by an open in the 1.8-ohm resistor. Who is correct?

25. During replacement of a blend door actuator, Technician A says that after replacing the actuator, one procedure for recalibrating the control module would be to remove the fuse for the module for at least 60 seconds, then replace the fuse and perform an operational test of the system. Technician B says that after installing the actuator, the control module will automatically know what the step the actuator is on and there is no need for calibration. Who is correct?

Click submit and your anwsers and results will be emailed to you, Good Luck!!!

Pages: 1 2 3