Operating systems and related controls diag and repair Flashcards
1
Q
- An A/C compressor clutch does not engage. Tech A says that an open high pressure cutout switch could be the problem. Tech B says a blown compressor clutch diode could be the cause. Which tech is correct?
A
a
2
Q
- Tech A says that the A/C compressor clutch may not engage if the steering wheel is being turned sharply and the vehicle is equipped with power steering. Tech B says that the A/C compressor clutch may not engage if the refrigerant system is low on charge. Which tech is correct?
A
c
3
Q
- A pop is heard from the radio speakers occasionally when the defroster or A/C is selected. Tech A says that the compressor clutch clamping diode may be blown. Tech B says that the A/C compressor clutch may have a poor electrical ground connection. Which tech is correct?
A
a
4
Q
- A reduced amount of airflow from the A/C vents is being discussed. Tech A says that the evaporator could be clogged as a result of a small refrigerant leak causing oil to trap and hold dirt. Tech B says that the blower motor ground connection could have excessive voltage drop. Which tech is correct?
A
c
5
Q
- Tech A says that an electrical open in the low pressure switch can prevent the compressor from working. Tech B says that the compressor may not operate at low outside temps depending on the pressure sensed by the low pressure switch. Which tech is correct?
A
c
6
Q
- Tech A says that the voltage to the A/C compressor may be turned off when some vehicles are accelerating rapidly. Tech B says that a fault in the power steering pressure switch could prevent the A/C compressor from operating. Which tech is correct?
A
c
7
Q
- An auto A/C system is being diagnosed for cooler than the set temp. Tech A says that a blocked inside air temp sensor could be the cause. Tech B says that a blocked sun load sensor could be the cause. Which tech is correct?
A
a
8
Q
- Refer to book
A
a
9
Q
- Refer to book
A
a
10
Q
- A blower motor stopped working on all speeds. A tech tested the motor touching a jumper wire from the battery positive terminal to the motor power terminal and the motor ran. Tech A says that the motor should be checked using a fused jumper lead to test for excessive current draw. Tech B says that the resistor pack and/or relay are likely to be defective. Which tech is correct?
A
c
11
Q
- A blower motor is drawing more than the specified current. Tech A says the blower motor ground connection could be corroded. Tech B says that the blower relay is shorted. Which tech is correct?
A
d
12
Q
- An older vehicle is being diagnosed. The airflow from the blower motor goes mostly to the defrost ducts regardless of the position of the controls. Tech A says that the recirculation door may be stuck. Tech B says that the vacuum source for the mode doors may be leaking. Which tech is correct?
A
b
13
Q
- A blower is running slowly on all speeds. What is the most likely cause?
a. blown resistor
b. worn/dry bearings in the motor
c. bad fan switch
d. open ignition switch
A
b
14
Q
- refer to book
A
d
15
Q
- A vehicle equipped with auto climate control was involved in a minor front end collision. Afterward the system stopped cooling. What is the most likely cause?
a. reduced airflow through the radiator
b. air trapped in the refrigerant system
c. a defective blower motor resistor
d. a broken ambient air temp sensor
A
d
