Chapter 15 Refrigeration System Diagnosis and Leak Detection 249
Review Questions—Chapter 15
Please do not write in this text. Write your answers on
a separate sheet of paper.
1. Strategy-based diagnostics involves reasoning through
a problem in a ______ of steps.
2. List in order the seven step troubleshooting process.
3. Try to talk to the vehicle driver to fi nd out the ______
complaint.
4. If the brakes are almost completely inoperable, should
you go on a road test?
5. If you do not locate the real HVAC system problem,
what will happen?
6. The refrigerant system must be ______ for any leak
testing procedure to work.
7. The ______ on some vehicles are disabled by the
engine control computer if the refrigeration system
loses its charge.
8. The most effective leak detector is the ______ type.
9. A troubleshooting ______ will often simplify
diagnosis.
10. ______ is very important in the troubleshooting
process.
ASE Certifi cation-Type Questions
1. All of the following are good questions to ask the driver
to help with diagnosis, except:
(A) does it happen whenever the engine is running?
(B) do you hear any unusual noises?
(C) how do you plan to pay for this?
(D) does the air come out of the vents or somewhere
else?
2. Technician A says if the vehicle has been retrofi tted,
the service fi ttings should be different from the original
fi ttings. Technician B says if the vehicle has been
retrofi tted, a retrofi t label should be installed under the
hood. Who is right?
(A) A only.
(B) B only.
(C) Both A and B.
(D) Neither A nor B.
3. A good refrigerant identifi er will be able to check for
all of the following, except:
(A) unknown refrigerants.
(B) unknown refrigerant oils.
(C) R-22 blends.
(D) contamination by unknown gases.
4. Technician A says high refrigeration system static
pressure indicates the vehicle has been retrofi tted.
Technician B says low refrigeration system static pres-
sure indicates a refrigeration system leak. Who is right?
(A) A only.
(B) B only.
(C) Both A and B.
(D) Neither A nor B.
5. All of the following are preliminary steps for the
refrigeration system performance check, except:
(A) set the parking brake.
(B) install a temperature gauge in the vent nearest
the evaporator.
(C) turn the HVAC control panel settings to the off
position.
(D) open the front windows.
6. If during the refrigeration system performance test you
notice the cooling fan(s) are not operating, which of
the following should you do next?
(A) Stop the performance test.
(B) Lower the engine speed to idle.
(C) Add coolant to the engine radiator.
(D) Turn the HVAC switch to vent.
7. Technician A says disconnecting the blower on a
system with an evaporator pressure control device
should cause the evaporator pressure to drop to
about 28-30 psi (193-207 kPa). Technician B says
disconnecting the blower on a system with an
evaporator pressure control device should make the
clutch cycle off in about 30 seconds. Who is right?
(A) A only.
(B) B only.
(C) Both A and B.
(D) Neither A nor B.
8. Refrigeration system pressures are correct on a cycling
clutch type refrigeration system. No cool air is coming
from the vents. Which of the following is the least
likely cause?
(A) Blend door cable broken.
(B) Dirt on the evaporator.
(C) Disconnected vacuum line at the heater/air con-
ditioner door.
(D) Plugged orifi ce tube.