ASE Test Preparation - A7 Study Guide Heating & A/C
(Motor Age Training) 2025-2026
1. When the defrost setting is selected, the com- True
pressor operates.
(True or False)
2. R744 refrigerant is pure CO2 True
(True or False)
3. Technician A says on R134a systems, you may Both Technician A & B
not find any evidence of oil, even with a leak,
because the lubricant is water soluble, and
could wash away.
Technician B says never use compressed air to
leak test or pressure test an R134a system.
Which technician is correct ?
4. Technician A says when checking for a leak Both Technician A & B
using an Electronic Leak Detector, you check
from the bottom to the top of the AC compo-
nent area.
Technician B says most OEMS (original equip-
ment manufacturers) recommend using an
Electronic Leak Detector.
Which technician is correct ?
5. Technician A says you can find the refrigerant Both Technician A & B
charge amount on a decal under the hood.
Technician B says the best way to make
sure the air-conditioning system is properly
charged is to remove all refrigerant from the
system and reinstall the proper amount of
refrigerant.
, ASE Test Preparation - A7 Study Guide Heating & A/C
(Motor Age Training) 2025-2026
Which technician is correct ?
6. An Automatic Temperature Control system Technician B only
that uses a BCM (Body Control Module) is be-
ing diagnosed on a 2008 vehicle using a scan
tool.
Technician A says you need a laptop computer
with software to diagnose any of these sys-
tems.
Technician B says you connect the scan tool,
turn on the ignition and use the menus to find
your system and tests.
Which technician is correct ?
7. An ATC (Automatic Temperature Control) sys- Both Technician A & B
tem is being diagnosed for a high air outlet
temperature.
Technician A says it is possible for a malfunc-
tioning ATC control system to prevent correct
operation even when the refrigerant system is
operating to specs.
Technician B says you should use a diagnostic
scan tool or laptop computer to identify ATC
problems.
Which technician is correct ?
8. Which of the following is the most important Air gap
measurement done when replacing a com-
pressor clutch?
, ASE Test Preparation - A7 Study Guide Heating & A/C
(Motor Age Training) 2025-2026
a. Coil voltage drop
b. Coil Current (ampere) draw
c. Air gap
d. Coil resistance
9. All of the following could cause the high side Broken compressor reed valve
pressure in an AC system to be higher than
normal, EXCEPT:
a. Refrigerant overcharge
b. Restricted condenser air flow
c. Restricted evaporator air flow
d. Broken compressor reed valve
10. Technician A says the pressure sensor disen- Technician A only
gages the compressor when low pressure is
sensed because low refrigerant flow could re-
sult in a lack of lubrication and seize the com-
pressor.
Technician B says air conditioning systems us-
ing a multi-pressure switch will display a data
line for system pressure on the scan tool DATA
parameter list.
Which technician is correct ?
11. Which of the following refrigerant oil is recom- ND-11
mended for use in a hybrid electric compres-
sor?
a. ND-10
b. ND-11
, c. ND-9
d. ND-8
12. On a manual air conditioning system with- Technician A only
out automatic control, the compressor clutch
does not operate.
Technician A says there is a failed compressor
thermal protector.
Technician B says there is an incorrectly ad-
justed temperature door.
Which technician is correct ?
13. All of the following could cause compressor Clutch air gap
drive belt edge wear, EXCEPT:
a. Clutch air gap
b. Bent mounting bracket
c. Damaged pulley
d. Worn pulley bearing
14. All of the following statements related to com- Sound can be heard when a compres-
pressors with damper limiter pulleys are cor- sor pulley engages and disengages.
rect, EXCEPT:
a. The pulley is attached to the compressor
shaft by spokes that break if the compressor
locks.
b. Sound can be heard when a compressor
pulley engages and disengages.
c. If the pulley breaks, the compressor and the
pulley are replaced as a unit.
d. If the pulley breaks, the pulley freewheels
on the compressor shaft.
(Motor Age Training) 2025-2026
1. When the defrost setting is selected, the com- True
pressor operates.
(True or False)
2. R744 refrigerant is pure CO2 True
(True or False)
3. Technician A says on R134a systems, you may Both Technician A & B
not find any evidence of oil, even with a leak,
because the lubricant is water soluble, and
could wash away.
Technician B says never use compressed air to
leak test or pressure test an R134a system.
Which technician is correct ?
4. Technician A says when checking for a leak Both Technician A & B
using an Electronic Leak Detector, you check
from the bottom to the top of the AC compo-
nent area.
Technician B says most OEMS (original equip-
ment manufacturers) recommend using an
Electronic Leak Detector.
Which technician is correct ?
5. Technician A says you can find the refrigerant Both Technician A & B
charge amount on a decal under the hood.
Technician B says the best way to make
sure the air-conditioning system is properly
charged is to remove all refrigerant from the
system and reinstall the proper amount of
refrigerant.
, ASE Test Preparation - A7 Study Guide Heating & A/C
(Motor Age Training) 2025-2026
Which technician is correct ?
6. An Automatic Temperature Control system Technician B only
that uses a BCM (Body Control Module) is be-
ing diagnosed on a 2008 vehicle using a scan
tool.
Technician A says you need a laptop computer
with software to diagnose any of these sys-
tems.
Technician B says you connect the scan tool,
turn on the ignition and use the menus to find
your system and tests.
Which technician is correct ?
7. An ATC (Automatic Temperature Control) sys- Both Technician A & B
tem is being diagnosed for a high air outlet
temperature.
Technician A says it is possible for a malfunc-
tioning ATC control system to prevent correct
operation even when the refrigerant system is
operating to specs.
Technician B says you should use a diagnostic
scan tool or laptop computer to identify ATC
problems.
Which technician is correct ?
8. Which of the following is the most important Air gap
measurement done when replacing a com-
pressor clutch?
, ASE Test Preparation - A7 Study Guide Heating & A/C
(Motor Age Training) 2025-2026
a. Coil voltage drop
b. Coil Current (ampere) draw
c. Air gap
d. Coil resistance
9. All of the following could cause the high side Broken compressor reed valve
pressure in an AC system to be higher than
normal, EXCEPT:
a. Refrigerant overcharge
b. Restricted condenser air flow
c. Restricted evaporator air flow
d. Broken compressor reed valve
10. Technician A says the pressure sensor disen- Technician A only
gages the compressor when low pressure is
sensed because low refrigerant flow could re-
sult in a lack of lubrication and seize the com-
pressor.
Technician B says air conditioning systems us-
ing a multi-pressure switch will display a data
line for system pressure on the scan tool DATA
parameter list.
Which technician is correct ?
11. Which of the following refrigerant oil is recom- ND-11
mended for use in a hybrid electric compres-
sor?
a. ND-10
b. ND-11
, c. ND-9
d. ND-8
12. On a manual air conditioning system with- Technician A only
out automatic control, the compressor clutch
does not operate.
Technician A says there is a failed compressor
thermal protector.
Technician B says there is an incorrectly ad-
justed temperature door.
Which technician is correct ?
13. All of the following could cause compressor Clutch air gap
drive belt edge wear, EXCEPT:
a. Clutch air gap
b. Bent mounting bracket
c. Damaged pulley
d. Worn pulley bearing
14. All of the following statements related to com- Sound can be heard when a compres-
pressors with damper limiter pulleys are cor- sor pulley engages and disengages.
rect, EXCEPT:
a. The pulley is attached to the compressor
shaft by spokes that break if the compressor
locks.
b. Sound can be heard when a compressor
pulley engages and disengages.
c. If the pulley breaks, the compressor and the
pulley are replaced as a unit.
d. If the pulley breaks, the pulley freewheels
on the compressor shaft.
