HVAC
On vehicles equipped with the auto start-stop feature, such as the 2014 fusion, the cabin heater coolant pump will only operate when:
the engine coolant temperature is above 60 C ( 140 F )
Select the correct statement related to resistor blower controls.
the lowest speed setting places the entire pack in series with the motor, limiting current flow and the speed of the blower.
which of the following statements does not apply to the heated seat systems?
the rear heated seat system is controlled by two rear heated seat modules
which of the following statements does not apply to the evaporator?
the refrigerant leaves the evaporator as a liquid
which parts should be checked first for leaks?
the seals and O-rings
latent heat of vaporation
the specific amounnt of heat energy needed to change a liquid to a vapor
latent heat condensation
the specific amount of heat energy released as a vapor changed to liquid
what occurs when the operator takes control of the mode door while the system is in auto mode?
the system continues to control the blower and blend door and attempts to maintain the set temperature
which of the following is not an effect of contaminants entering the system?
they will increase the operational efficiency of the system
sensible heat
this describes the heat that promotes a change in temperature of a substance
temperature
this is the intensity level of heat and can be measured with a thermomer
A day when the outside temperature is 21C with 30% humidity feels hotter than a day with 32C temperature at 5% humidity
true
Carefully check the wiring and electrical connections at the components because in most cases the fault will be found in this area.
true
During the A/C testing set-up procedure the climate control module should be placed in the mono mode on vehicles equipped with a DATC System.
true
Most electronic and fluorescent hand-held leak detectors certified for R-1234yf work on both R-134a and R-1234yf refrigerant with similar sensitivity
true
On hybrid vehicles, the cabin heater coolant pump will provide coolant to engine components when the engine is running.
true
On some vehicles, such as the 2013 Fiesta, HVAC module DYC are retrieved using buttons on the HVAC control head
true
The high-pressure cutoff switch is mounted on the discharge line between the compressor and the condenser.
true
The sealant detection kit and refrigerant analyzer are used to prevent damage to recovery equipment.
true
True or False: When the ECM receives a compressor request from the HVAC module, it must verify its own enabling criteria before commanding the relay.
true
The heater core is an air to liquid heat exchanger similar to a radiator?
False
R-12 and R1234yf leak detector
GE-39400-A uses heated diode sensor to detect leaks as small as 14g per year
R-134a and R-1234rf leak detector
GE-50078 uses an infrared type sensing element to detect leaks as small as 4g per year
Radiator
Is a liquid to air heat exchanger that reduces coolant temperature by transferring heat from the radiator to the outside air
Heater core
Is a liquid to air heat exchanger, air passes through the heater core, heat is transferred from the engine coolant to the air inside the climate control housing.
thermostat
Is a temperature dependent valve that opens and closes according to the engine coolant temperature to regulate the flow of coolant through the radiator and back to the engine
Which of the following statements does not apply when servicing vehicles with an electric A/C compressor?
PAG oil will improve the function of the electric windings in the electric A/C compressor.
The cabin heater coolant temperature sensor provides coolant temperature information to what module.
PCM
which module is used by the climate controlled seats system to heat or cool the rear seats?
PCSM-2
enhanced glasses
Protects eyes from ultraviolet light and enhances the image
Accumulator
Protects the compressor from drawing in liquid
variable displacement orifice tube (VDOT)
The compressor remain engaged whenever the a/c mode is selected. A fixed size' flow control device is used, while the compressor varies its output.
latent heat
The energy needed to change an object form one state to another without changing temperature is called
which statement is false regarding the refrigerant filter in the GE-50300?
The machine will lock down after 200 kg ( 440 lbs ) or refrigerant have been recovered
The coolant bypass solenoid valve provides a second path for coolant to flow between the engine block and the:
Thermostat housing
cycling clutch orifice tube (CCOT)
These systems cycle the compressor on and off to maintain the refrigeration cycle within predetermined limits.
The evaporator consist of ____________ fins that rapidly transfer heat to refrigerant- carrying coils.
aluminum
what actuator does the rear climate control system use to reach the requested air temperature?
auxiliary temperature blend door
The first door on the 2-door system controls airflow to the panel vents. where does the second door control airflow?
between the floor vents and the defrost vents
The 2010 F-super Duty electric booster supplemental heater system will not operate when there are Continuous Memory Diagnostic trouble codes ( CMDTCs ) related to the function of what system?
charging
the efficient operation and service life of any air conditioning system:
depends upon the chemical stability in refrigeration system
When testing seat components on vehicles equipped with seat mounted side airbags you must first:
depower the supplemental restraint system ( SRS )
refrigerant oil is hygroscopic, meaning it attracts moisture, therefore,
do not open the oil container until the service procedure requires oil
scroll-type
does not make use of pistons and a swash or wobble plate
when the defrost setting is selected, the recirculated function is activated on the air inlet door actuator will only allow recirculated air into the passenger compartment.
false
fluorescent dye
glow yellow-green under ultraviolet light
what causes a liquid to change into a vapor?
heat
latent or hidden heat occurs when:
heat added to the boiling water is hidden form the thermometer
When a restriction is in the liquid and discharge line between the condenser and high pressure service port, high side pressure is:
high
When the compressor is faulty high side pressure in normal to low and the low side pressure is:
high
a system that is overcharged may have ______________ system pressure
higher than normal
increased
if the amount of pressure placed on a liquid is increased, the resulting boiling point of the liquid is:
correct -the internal scale on the cooltech GE-48000 may need to be calibrated periodically -the machine shows a filter-drier usage message and will stop working at 68 kg ( 150 lbs. ) - the GE-48800 does not contain a printer
incorrect - The GE-48800 contains an integrated refrigerant identifier -The Cooltech GE-48800 vacuum pump oil needs to be changed after 45 kg ( 100 lbs ) of refrigerant has been recovered -the Cooltech GE-48800 is used to recover, recyclek, and recharge R-1234yf refrigerant
increase
increasing the pressure applied on a gas causes the temperature of the gas to:
Which type of electric actuator has internal logic?
internally-driven
The cabin heater diverter valve is controlled by the PCM an is used to :
isolate the heater circuit form the engine cooling circuit to improve heater performance.
what process causes matter to change states without change in temperature
latent heat
which of the following statements correctly describes the receiver and dehydrator?
located on the high-pressure side of the refrigeration system
which of the following is not a feature of the ACR2000?
locks up once 136 kg ( 300 lbs ) of refrigerant have been recovered
An undercharged refrigerant system will show high side pressure being normal to low and low side pressure:
low
The two major functions of the compressor are to circulate refrigerant and to compress
low pressure refrigerant vapor into hot, high pressure vapor
The de-stroking or full stroking of the variable displacement compressor is determined by:
low side pressure
what is measured during the dynamic performance stage?
low- and high side pressures
the static pressure check is the initial procedure that provides information to determine whether there is enough _______________________ in the system to complete the remainder of the a/c performance test
refrigerant
Latent heat of vaporization occurs in the refrigerant system when:
refrigerant changes state from a low-pressure liquid to a low-pressure vapor inside the evaporator.
ambient air
refrigerant cycles through the system and heat is released.
Air entering the passenger compartment
refrigeration system are used to transfer heat form this to the refrigerant.
evaporator thermistor
regulates evaporator by cycling the compressor clutch to prevent evaporator freeze-up
the variable displacement thermostatic expansion valve system uses a variable displacement compressor with TXV. The compressor clutch '___________________________ whenever the A/C mode is selected.
remains engaged
recovery and recharging station
requires a dedicated machine for each type of refrigerant being serviced
what style of electrically powered compressor is used on hybrid and electric vehicles?
scroll
which of the following is a characteristic of the ACR2000
services vehicles using R-134a refrigerant
The climate control system uses vehicle speed information to:
stabilize the outside temperature reading.
The pressure reading taken when the A/C system is not operating is called
static pressure
which style of actuator uses a single power feed and four low side circuits connected to the climate control module to control the position of the actuator door?
stepper motor
which of the following inputs is used by the controller to reach and maintain set temperature?
sun load
which of the following is not a sensor input used by the HVAC control module in automatic mode?
sun load exterior temperature interior temperature window position *
thermometer
temperature is the intensity level of heat, and can be measured with a:
The variable displacement compressor de-stroke test can only be conducted when:
the TXV shuts down to reduce discharge pressures under low heat loads
blended air-mix
the air distribution subsystem of the HVAC assembly is this type of system that directs conditioned air through the outlets.
british thermal units
the amount of heat energy needed to raise the temperature of 1 pound of water 1 F at sea level
Variable Displacement Thermostatic Expansion Valve (VDTXV)
the compressor remains engaged whenever the a/c mode is selected. The compressor varies its output and flow control device of refrigerant flowing into the evaporator.
Latent heat of condensation occurs in the refrigerant system when:
the condenser extracts heat from the refrigerant into the outside air
correct -a half-pound of refrigerant may need to be added to effectively perform a leak test -a system that is overcharged may have higher than normal system pressure - to prepare a vehicle for the static pressure check, park the vehicle inside or in a shaded area
wrong - a pressure reading lower than normal indicates a system may be overcharged - the static pressure check does not need to be performed in order to complete the remainder of the a/c performance test
When measuring the resistance of the backrest or cushion blower motor, the positive lead of the ohmmeter must be connected to the blower motor voltage pin and the negative lead to blower motor negative pin
true
When the factory remote start feature is activated, the rear defroster, heated mirrors, and heated or climate controlled seats do not automatically activate at moderate temperatures.
true
climate controlled seats are available in the second row seating position.
true
if the receiver/drier is saturated with water, the discharge air will start out cold but will warm up after 5 to 10 minutes.
true
it is not necessary to add dye after flushing the refrigerant system because a new suction accumulator or receiver/drier containing a fluorescent dye wafer is installed as part of the flushing procedure.
true
selecting the highest heat setting on the climate control module in on condition that must be met to operate the electric booster heater system
true
the high voltage battery must be full charged when diagnosing the cabin coolant system.
true
when recording refrigerant pressure you should only take refrigerant pressure readings when the compressor is engaged.
true
dye injector
used to locate leaks in the air conditioning system
recovery equipment
used when contaminated R-1234yf is detected.
which of the following statements does not apply to a tri-zone auxiliary climate control system?
uses an EMTC system to control air temperature in the rear passenger compartment.
oil injector
uses labels to identify PAG and POE types to prevent cross-contamination.
which of the following processes should be performed first when diagnosing the heating system?
verify the customer concern
Heat flow is the naturally occurring transfer of heat energy from a ________________ object to a relatively ____________ object.
warm, cooler
What does a zone classification table help to plot?
where a vehicle's high- and low-side pressures fall
Coolant Pump
Are mechanically controlled devices that circulate coolant through the radiator and back to the engine.
A variable displacement compressor may fail to go in full stroke mode:
* all of the above - if the system is undercharged -has a struck closed or restricted thermostatic expansion valve ( TXV ) - during a low heat load conditions and if there is a low or high side blockage
which of the following statements related to safety precautions when working with refrigeration systems are true?
- always work in a well-ventilated area -R-1234yf is heavier than air and accumulates in low areas -only use tools dedicated for the type of refrigerant being serviced -using cold water, flush any area that has been in contact with either refrigerant or lubricant
The air distribution system is a self-contained housing that provides the following 3 main functions:
- assembly provides a sealed path for airflow from the air inlets to the appropriate air outlets - blend door/vale controls the temperature of the air delivered to the vehicle -blower controls the volume of airflow
the auto start-stop system may automatically restart the engine when:
- blower speed is increased - the power windows are operated. - an additional vehicle accessory is plugged into a power outlet - all of the above *
which of the following statements correctly describe thermal expansion valves ( TXVs)
- both internal and external-sensing TXVs regulate the size of the orifice, thereby controlling the amount of refrigerant flowing in and out of the evaporator. - the valve converts high-pressure liquids refrigerant from the condenser to a low-pressure liquid refrigerant -TXVs are installed at the evaporator inlet and outlet fittings
Which of the following Statements are true regarding heat flow?
- heat always flows from an object containing more latent heat to an object with less latent heat -objects with insulating qualities slow down heat transfer -the greater the difference in temperature, the quicker the heat transfer rate -heat flow is the naturally occurring transfer of heat form a warmer object to a relatively cooler object.
when the PCM receive an A/C request signal, it uses what information to determine if the A/C compressor should be engaged?
- refrigerant pressure, engine coolant or cylinder head temperatures - ambient air, and evaporator discharge temperatures - throttle position sensor signal - all of the above*
which of the following statements are true regarding the tool for servicing HVAC system?
- the GE-50300 or GE-50300-A may be used to service HVAC systems filled with R-1234yf -the orifice tube remover is used to remove the orifice tube from the condenser to evaporator line -contaminated r-1234yf must be recovered and disposed of at an EPA-approved facility -the oil injector adapter may have a tag indicating the type of oil, PAG or POE
when automatic control is selected, the only input required from the operator is the desired interior temperature ( set temperature ). Which of the following statements correctly describe automatic control?
- the controller will automatically select the appropriate air intake to maintain the set temperature. -the controller will automatically select the appropriate discharge air temperature to maintain the set temperature. -the controller will automatically select the appropriate air discharge outlet to maintain the set temperature. The controller will automatically select the appropriate fan speed to maintain the set temperature.
which are the most common types of blower controls?
-Resistor pack and relay -external blower control module -internal blower control module
A heater, ventilation, and air conditioning ( HVAC ) system can be divided into the following three sub-system
-engine cooling -refrigeration -air distribution
Thermal expansion valves may fail due to clogging of the inlet screen caused by which of the following?
-loose desiccant material -refrigerant contamination -internal compressor failure -corrosion
which of the following statements correctly describes condenser concerns/faults?
-partial restriction may cause ice, frost, or a temperature change to occur immediately after the restriction. -restricting airflow across the condenser results in high discharge pressure and poor passenger compartment cooling -a condenser flow restriction may result in excessive compressor discharge pressure
the a/c performance test measure the a/c system operation efficiency by identifying
-pressure at the low- and high-pressure sides of the refrigerant system during static and operating conditions -discharge temperatures from the vents during specific operating conditions -ambient air temperature and humidity
which of the following statements correctly describe oils and lubricants?
-refrigerant carries a charge of lubricating oil throughout the refrigeration system to lubricate moving parts. -it is recommended that compressor oil level be checked when there is evidence of major loss of system oil -compressor lubrication begins when refrigerant enters the compressor
which of the following statements correctly describe an orifice tube?
-regulates the flow of refrigerant into the evaporator -the refrigerant flow rate is determined by the diameter of the orifice -an orifice tube is located and the evaporator inlet -orifice tube failure is indicated by high discharge pressure and insufficient evaporator cooling.
which of the following statements are functions of the accumulator?
-separates the vapor from the liquids and oil -helps protect the compressor from any damage resulting from attempting to compress liquid -releases the vapor to the compressor -filters the refrigerant as it circulates throughout the system
Which of the following statements are true regarding HFO-1234yf refrigerant?
-specific leak testing procedures are mandatory when testing HFO-1234yf refrigerant -HFO-1234yf refrigerant requires a dedicated contaminated refrigerant reclaiming machine -HFO-1234yf refrigerant requires the use of a specific charge and recovery and recycling equipment with a integrated refrigerant identifier
1 2 3
1. liquid refrigerant flows from the TXV or orifice into the evaporator creating a cool evaporator surface. 2. as the passenger compartment air stream flows over the evaporator fins, the air transfers its heat to the cooler surfaces of the fins and on to the refrigerant. 3. when the liquid refrigerant receives enough heat, it changes states to a low - pressure refrigerant vapor.
How much higher should the center register air temperature reading be than the low side pressure reading?
10 to 18 degrees
When using active commands to test heat or cool mode operation, the driver climate control seat module ( DCSM ) only operates the system in :
15 second intervals
Inputs -set temperature -temperature sensors -a/c sensors - sun load sensor
Automatic controls -blower speed - blend door -inlet door - a/c compressor
when conducting a cooling system pressure test, the pressure gauge should hold at maximum pressure for approximately how long?
2 minutes
During remote start the climate controlled seat system will activate the cooled seat function when ambient air temperature is greater than:
27C ( 80F )
the electric booster heater system used on the 2014 fiesta will activate two relays to power how many heating elements inside the electric booster heater?
3
when storing refrigerant, do not exceed what percentage of the cylinder's refill capacity ?
60%
The refrigerant analyze will illuminate a red FAIL LED if purify level of refrigerant is below what percentage by weight?
98%
the auxiliary heater assembly uses what module to control the electrical supply to the heating elements?
AHCM
which component in the electric booster supplemental heater system uses a current PID to verify that the current level at the component is above 50 amps
Auxiliary heater control module ( AHCM )
what conditions must be met when using an infrared refrigerant leak detector or dual mode refrigerant gas and UV Dye leak detector?
Both - refrigerant pressure should be between 413-551 kpa ( 50.9 - 79.91 psi ) - ambient air temperature is 24 C ( 75F with the engine off and cool.
The 1.6 GTI engine uses the no flow coolant strategy in the engine block to
Both a and B ( quickly warm up the cylinder heads and engine block, supply coolant from the cylinder head water jacket to the heater core for cabin heating
The 1.0 GTDI engine used in the 2014 Fiesta is equipped with an electric coolant pump. what conditions must be met for the PCM to activate the electric coolant pump?
Both a and b ( the engine has been shutdown, the engine has operated at a high load for an extended period of time.
true
By compressing a gas or vapor and concentrating heat into a smaller area, the temperature can be increased without adding extra heat.
which module is used by the climate controlled seats system to hear or cool the front seats?
DCSM
Metering Device
Divides high pressure, high temperature side from low pressure, low temperature side
Compressor
Draws in low pressure vapor and discharges high pressure, high temperature vapor
Evaporator
Enters as low pressure, low temperature liquid and discharges low pressure, low temperature vapor
When the factory remote start feature is activated and the DATC system is in auto mode, which of the following readings is not used to determine climate control demand
Evaporator temperature
The electronic control methods of air door/valve control use electric motors to provide variable positioning of the doors and valves. which two control methods control the electric motors?
Externally driven and internally driven
what control devices activate the front heated seat system?
FCIM FDIM SWITCHES all of the above*
which of the following devices provide an interface to control the operation of the front and rear climate controlled seats?
FDIM HVAC module RHVAC all of the above*
which of the following modules cycle the heater circuits on and off to maintain the heated seat temperature?
HVAC FCIM Heated seat module All of the above*
What happens to high side pressure when a variable displacement compressor de-strokes in the refrigerant system?
High side pressure decreases
Degas bottle
Is attached to the radiator. It hold excess or overflowing coolant, removes air from the cooling system, allows for expansion and system pressurization, and used to replenish coolant in the system.
How does the HVAC control module request compressor operation?
Sends a request to the engine control module using a serial data or a dedicated circuit
the A/C system is divided into two sides: a low-pressure or suction side and a high-pressure or discharge side. what component separates the two sides?
TXV or the fixed orifice tube
A/C Cycling Switch
The A/C cycling switch monitors low side pressure at the accumulator to prevent evaporator freezing.
which modules must confirm the correct enabling criteria is met before the compressor may be commanded on ?
The HVAC control module and the engine control module
A/C Pressure Switches
The PCM uses various types of switches or sensors to monitor refrigerant pressure. The PCM will not engage the compressor if refrigerant pressures are excessively high or low.
Coolant shut off solenoid valve
Used to control coolant flow to the thermostat housing, coolant pump, engine block, cylinder heads, heater core, turbocharger, transmission oil cooler, and engine oil cooler.
Coolant Bypass Solenoid Valve
Used to provide a second path for coolant to flow between the engine block and thermostat housing. ( PCM opens the the solenoid valve to increase coolant flow through the block to reduce pressure and temperature fluctuations )
which of the following statements does not apply to the suction accumulator?
Uses a desiccant bag to remove moisture from the refrigerant on the high side of the system
Engine Coolant or cylinder head temperature and ambient air temperature
Using sensor located in the engine compartment to monitor cylinder head and ambient air temperature. The PCM will not engage the compressor if engine coolant temperature or cylinder head temperature is excessively high or when the ambient air temperature is below approximately 2C ( 35.6 F )
pressure senor
a 3-wire transducer that is an input to the engine control module for various components
in order to effectively perform a leak test, it may be necessary to add up to ____________________________
a half-pound of refrigerant
scroll-type compressor
a pressure-activated control valve diverts high pressure vapor form the bleed ports back to the suction side when heat load is low
What does a significant temperature drop or abnormal frost areas indicate?
a restriction
what may be indicated by a significant temperature drop or the presence of abnormal frost areas?
a restriction
what is the main difference between a variable scroll and fixed scroll compressor ?
a variable scroll uses a control valve to adjust output capacity.
which diagnostic is used when a pooling condition is not caused by the blend door?
a/c refrigeration performance test
Poly-alkaline Glycol ( PAG ) oil should not be exposed to air longer than necessary to service because it:
absorbs water vapor
in addition to reducing the operational efficiency of the system, causing corrosion, and accelerating wear, contaminants also:
affect the temperature/pressure relationship of the refrigerant
how often must the oil be changed on the Cooltech GE-48800 vacuum pump?
after every 10 hours of operation
which statement is true regarding the refrigerant filter in the GE-50300?
after filter replacement, the serial number must be entered to unlock the machine
Evacuation is the process of pulling a vacuum on an a/c system to remove
all of the above* - air - residual refrigerant - moisture
GM systems are referred to as _____________ systems, as all airflow travels through the evaporator first, with the temperature control blending the amount of air flowing through (or around ) the heater core to meet the temperature requirements.
blended air
When performing a A/C cooling coil coating treatment which of the following components should be removed if they are exposed to the blower motor airflow?
blower motor blower motor resistor blower motor speed controller all of the above*
Blower motor
blower motor circulates air through the heater core and the evaporator core housing
Technician A says the expansion valve uses an internal diaphragm filled with a temperature sensitive fluid to monitor evaporator temperature. Tech B says the expansion valve has a temperature sensing bulb located near the outlet of the evaporator. who is correct
both
Environmental orders are caused by an external source and are only detected when
both the vehicle windows are open the climate control system is drawing fresh air into the vehicle
When checking backrest and cushion seat heater mats for an open or short to ground, it is best to
both -move the seat heater mat being tested -sit in the seat to diagnose an intermittent open in the mat
The A/C pressure transducer is used by the PCM to monitor what pressure?
both refrigerant section pressure refrigerant discharge pressure
which of the following symptoms could cause a no flow condition through the heater core outlet hose?
both the heater core is clogged with contaminants an air pocket in the heater core
the climate control system adjusts the auxiliary door position to direct airflow to:
both , roof panel registers , floor ducts
which conditions must be met when diagnosing the electric booster supplemental heater system used on the 2013 escape or 2014 fiesta?
both, engine coolant temperature is below 60C ( 140 F ) ambient air temperature is below 10c ( 50F )
when the A/C system is placed in the panel mode, blended air is only available when:
both, A/C request button is selected, outside air temperature is above approximately 6C ( 43F )
to operate the climate control system during remote start, what should the climate control setting be placed in ?
both, AUTO mode, last setting mode
which supplemental heating system uses a heating element to warm the air in the HVAC housing?
both, electric booster heater, auxiliary heater assembly
changing the pressure of a liquid change its:
both, temperature, boiling point
how does the a/c performance test measures the a/c system's operating efficiency?
by identifying the ambient air temperature and humidity
when testing the cabin coolant heater, what other component in the cabin coolant heater system must be operating to prevent damage to the cabin coolant heater?
cabin heater coolant pump
which of the following components cannot be checked using active commands?
cabin heater coolant temperature sensor
what are the three control methods used for air doors?
cable, vacuum, and electronic
to prevent the entry of dirt, moisture or foreign material:
cap, plug, or tape both sides of the connection immediatly
when the A/C system is placed in the MAX A/C mode, the climate control module will:
close the air inlet door preventing outside air from entering the vehicle
variable-displacement compressor
compression is controlled by the position of a bellow-actuated control valve that dictates pressure in the crankcase of the compressor
all cycling clutch orifice tube ( CCOT ) refrigerant system use fixed displacement compressors and an orifice tube. these system also include a _________,_____________,______________, and various control components
condenser, accumulator, evaporator
variable displacement
contains pistons and utilizes a wobbler plate instead of a swash plate
fixed displacement
controlled by cycling on and off according to the pressure of the refrigeration system
Heat flow moves in three ways: radiation, conduction, or ____________
convection
the rear refrigeration system is a complete system because it contains a TXV and an evaporator connected to the front refrigeration system.
false
vehicles such as the fusion energi and c-max energi, use the cabin coolant heater system to provide the heater core with coolant to warm the passenger compartment when:
during all of these conditions: operating in pure electric mode the vehicle is remotely started the customer has activated the remote cabin preconditioning feature
when using the vacuum control method, vacuum actuators position the door. The vacuum is applied to the correct actuator based on the control head position selected, or _______________.
electric control for the vacuum solenoid
orifice tube remover
engages with the tangs and acts as a puller
The number keys of the recovery and recharging stations are generally use to enter the following information except:
engine speed
condenser
enters as high pressure, high temperature vapor, and discharges high pressure liquid
The _______________ cool and dehumidifies the air stream that enters the passenger compartment.
evaporator
which sensor is used to prevent evaporator freeze-up?
evaporator temperature sensor
General motors vehicles use a blended air-mix system. In this system all of the air passes through the __________________, and the blend door controls the outlet temperature by directing the correct amount of air through or around the ____________.
evaporator, heater core
Air enters the system either through the outside air door or inside air door. The volume of the air is determined by the speed of the blower motor. The blend door controls the temperature of air, directing air though the heater core for cooling and bypassing the heater core for heating
false
The A/C system has independent air distribution modes and blower motor controls for the driver or passenger.
false
The FDIM monitors the cushion temperature sensor and supplies current to the seat cushion and backrest heater mats until the desired temperature is reached.
false
all cabin coolant heater system testing procedure active commands to check the function of the components.
false
on vehicles equipped with a variable displacement compressor the PCM uses evaporator temperature sensor information to prevent icing of the evaporator core by cycling the compressor on and off
false
the cooling feature used in the climate controlled seats system only operates when the vehicle's A/C system is cooling the vehicle
false
the electric booster supplemental heater system is an engine coolant supplied device that heats the passenger compartment rapidly in cases of low ambient temperatures.
false
the electric booster supplemental heater system used on the 2010 F-super duty will not operate if the generator is operating above 75% capacity.
false
the rear climate control system uses an auxiliary air inlet door actuator to direct outside air into the passenger compartment.
false
ultraviolet light
makes seeing the dye easier
What are the two basic types of control system for air distribution?
manual and automatic controls
fixed-displacement compressor
meets A/C demand by cycling on and off according the pressure of the low side of the refrigeration system
when connected to the A/C system, the Neutronic quick detect A/C Sealant detector kit is designed to:
mimic an A/C leak
low-pressure cycling switch
monitors evaporator temperature and serves as an input to control the compressor clutch
what type of engine coolant can only be used in gasoline engines?
motorcraft specialty green engine coolant
Which type of PAG refrigerant compressor oil should be used when servicing an electric A/C compressor?
none of the above* motorcraft pag refrigerant compressor oil - heaavy truck pag refrigarant compressor oil -motorcraft electric a/c compressor pag oil
which of the following statements does not apply to the requirements for a/c system flushing?
oil in the refrigerant
high-pressure relief valve
opens and releases pressure to prevent compressor damage, under certain conditions
if the outlet temperature fails after operating the system for a total of 10 minutes, what are then used to determine diagnostic direction?
outlet temperatures and high- and low-side pressures
according to strategy-based diagnostic, what is the first step in diagnosing a HVAC concern?
perform the diagnostic system check- vehicle procedure
when conducting a cooling system pressure test, which of the following should be performed to obtain an accurate pressure reading?
press the plunger slowly when pressurizing the cooling system
The algorithm within the control head controls each of three main output sub-systems ( blower control, temperature door control, and mode door operation ) based on whether it must issue a cooling command or heating command. This is identified as
program number
The condenser is placed in front of the ____________________ to receive maximum airflow from vehicle movement and coolant fan operation .
radiator
The 2014 C-max uses a catalytic converter exhaust manifold with coolant passages to:
raise coolant temperature to expedite passenger compartment heating on hybrid electric vehicles
what module controls the operation of the rear heated seat system
rear heated seat module
