sensor NISSAN TEANA 2014 Service Manual

HA-42
< REMOVAL AND INSTALLATION >
HEATING AND COOLING UNIT ASSEMBLY
HEATER CORE : Removal and Installation
INFOID:0000000009463950
REMOVAL
1. Remove the heating and cooling unit assembly. Refer to HA-41, "HEATING AND COOLING UNIT
ASSEMBLY : Removal and Installation".
2. Remove the heater core pipes cover. Refer to HA-40, "Exploded View"
.
3. Disconnect the harness connector from the blower motor.
4. Remove the heater core.
INSTALLATION
Installation is in the reverse order of removal.
EVAPORATOR
EVAPORATOR : Removal and InstallationINFOID:0000000009463951
REMOVAL
1. Remove the heater core. Refer to HA-42, "HEATER CORE : Removal and Installation".
2. Remove the upper floor connecting duct (RH). Refer to HA-40, "Exploded View"
.
3. Remove the air mix door motor (driver). Refer to HAC-109, "AIR MIX DOOR MOTOR : Removal and
Installation - Air Mix Door Motor (RH)".
4. Remove the air mix door motor (passenger) (if equipped). Refer to HAC-109, "AIR MIX DOOR MOTOR :
Removal and Installation - Air Mix Door Motor (LH)"
5. Disconnect the harness connector from the intake sensor.
6. Remove the evaporator and expansion valve assembly.
INSTALLATION
Installation is in the reverse order of removal.
NOTE:
The evaporator can only be ordered as an assembly with the expansion valve.
EXPANSION VALVE
EXPANSION VALVE : Removal and Installation for Expansion ValveINFOID:0000000009463952
REMOVAL
1. Discharge the refrigerant. Refer to HA-23, "Recycle Refrigerant".
2. Remove the strut tower brace. Refer to FSU-19, "Exploded View"
.
3. Disconnect the low-pressure pipe from the expansion valve.
4. Disconnect the high-pressure pipe from the expansion valve.
5. Remove the expansion valve bolts.
6. Remove the expansion valve.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
After charging refrigerant, check for leaks. Refer to HA-21, "Leak Test"
.
Revision: November 20132014 Altima NAM

HAC-2
Diagnosis Procedure ..............................................55
U1010 CONTROL UNIT (CAN) .........................56
Description ........................................................... ...56
DTC Logic ...............................................................56
Diagnosis Procedure ..............................................56
B2578, B2579 IN-VEHICLE SENSOR ...............57
DTC Logic ............................................................ ...57
Diagnosis Procedure ..............................................57
Component Inspection ............................................58
B257B, B257C AMBIENT SENSOR .................60
DTC Logic ............................................................ ...60
Diagnosis Procedure ..............................................60
Component Inspection ............................................61
B2581, B2582 INTAKE SENSOR ......................63
DTC Logic ............................................................ ...63
Diagnosis Procedure ..............................................63
Component Inspection ............................................64
B2630, B2631 SUNLOAD SENSOR .................66
DTC Logic ............................................................ ...66
Diagnosis Procedure ..............................................66
Component Inspection ............................................67
B2632, B2633 AIR MIX DOOR MOTOR
(DRIVER SIDE) ............................................... ...
69
DTC Logic ............................................................ ...69
Diagnosis Procedure ..............................................69
B2634, B2635 AIR MIX DOOR MOTOR (PAS-
SENGER SIDE) ............................................... ...
71
DTC Logic ............................................................ ...71
Diagnosis Procedure ..............................................71
B2636, B2637, B2638, B2639, B2654, B2655
MODE DOOR MOTOR ................................... ...
73
DTC Logic ............................................................ ...73
Diagnosis Procedure ..............................................73
B263D, B263E, B263F INTAKE DOOR MO-
TOR ................................................................. ...
75
DTC Logic ............................................................ ...75
Diagnosis Procedure ..............................................75
B27B0 A/C AUTO AMP. ....................................77
DTC Logic ............................................................ ...77
Diagnosis Procedure ..............................................77
POWER SUPPLY AND GROUND CIRCUIT .....78
A/C AUTO AMP. .................................................... ...78
A/C AUTO AMP. : Diagnosis Procedure ................78
AIR MIX DOOR MOTOR (DRIVER SIDE) .............. ...78
AIR MIX DOOR MOTOR (DRIVER SIDE) : Diag-
nosis Procedure ................................................... ...
78
AIR MIX DOOR MOTOR (PASSENGER SIDE) ..... ...79
AIR MIX DOOR MOTOR (PASSENGER SIDE) :
Diagnosis Procedure ............................................ ...
79
MODE DOOR MOTOR ........................................... ...80
MODE DOOR MOTOR : Diagnosis Procedure .......80
INTAKE DOOR MOTOR ........................................ ...81
INTAKE DOOR MOTOR : Diagnosis Procedure ....81
A/C SWITCH ASSEMBLY .........................................82
A/C SWITCH ASSEMBLY : Component Function
Check ................................................................... ...
82
A/C SWITCH ASSEMBLY : Diagnosis Procedure ...83
BLOWER MOTOR .......................................... ...84
Diagnosis Procedure ............................................ ...84
Component Inspection (Blower Motor) ...................85
Component Inspection (Front Blower Motor Re-
lay) ....................................................................... ...
85
MAGNET CLUTCH ............................................87
Component Function Check ................................ ...87
Diagnosis Procedure ...............................................87
A/C SWITCH ASSEMBLY SIGNAL CIRCUIT ...88
Diagnosis Procedure ...............................................88
DOOR MOTOR ..................................................89
Diagnosis Procedure ............................................ ...89
DOOR MOTOR COMMUNICATION CIRCUIT ...91
Diagnosis Procedure ............................................ ...91
ECV (ELECTRICAL CONTROL VALVE) ..........92
Diagnosis Procedure ............................................ ...92
Component Inspection ............................................93
SYMPTOM DIAGNOSIS ............................94
HEATER AND AIR CONDITIONING SYSTEM
CONTROL SYMPTOMS ................................. ...
94
Diagnosis Chart By Symptom .............................. ...94
INSUFFICIENT COOLING .................................96
Description ........................................................... ...96
Diagnosis Procedure ...............................................96
INSUFFICIENT HEATING .................................98
Description ........................................................... ...98
Diagnosis Procedure ...............................................98
COMPRESSOR DOES NOT OPERATE ...........99
Description ........................................................... ...99
Diagnosis Procedure ...............................................99
REMOVAL AND INSTALLATION .............101
A/C SWITCH ASSEMBLY .............................. ..101
Removal and Installation .......................................101
A/C AUTO AMP. ............................................. ..102
Exploded View ..................................................... .102
Removal and Installation .......................................102
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM

HAC-3
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AMBIENT SENSOR ....................................... ..103
Removal and Installation .......................................103
IN-VEHICLE SENSOR ................................... ..104
Removal and Installation .......................................104
SUNLOAD SENSOR ...................................... ..105
Removal and Installation .......................................105
INTAKE SENSOR .......................................... ..106
Removal and Installation .......................................106
REFRIGERANT PRESSURE SENSOR ......... ..107
Removal and Installation .......................................107
DOOR MOTOR ............................................... ..108
Exploded View .................................................... ..108
INTAKE DOOR MOTOR ........................................ ..109
INTAKE DOOR MOTOR : Removal and Installa-
tion ...................................................................... ..
109
MODE DOOR MOTOR .......................................... ..109
MODE DOOR MOTOR : Removal and Installation ..109
AIR MIX DOOR MOTOR ....................................... ..109
AIR MIX DOOR MOTOR : Removal and Installa-
tion - Air Mix Door Motor (RH) ............................. ..
109
AIR MIX DOOR MOTOR : Removal and Installa-
tion - Air Mix Door Motor (LH) ............................. ..
109
MANUAL AIR CONDITIONER
PRECAUTION ................ ............................
110
PRECAUTIONS .............................................. ..110
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ..
110
Precaution for Work ..............................................110
Working with HFC-134a (R-134a) .........................110
Precaution for Service Equipment .........................111
PREPARATION .........................................113
PREPARATION .............................................. ..113
Special Service Tool ........................................... ..113
Commercial Service Tool ......................................113
SYSTEM DESCRIPTION ...........................114
COMPONENT PARTS ................................... ..114
Component Part Location ................................... ..114
Component Description .........................................115
SYSTEM ...........................................................117
System Diagram .................................................. ..117
System Description ...............................................117
Air Flow Control .....................................................118
Air Inlet Control .....................................................118
Air Outlet Control ...................................................118
Compressor Control ..............................................118
Door Control ..........................................................119
Temperature Control ........................................... ..121
OPERATION ...................................................122
Switch Name and Function ....................................122
DIAGNOSIS SYSTEM (BCM) .........................124
CONSULT Function (BCM - COMMON ITEM) ......124
CONSULT Function (BCM - AIR CONDITIONER) ..125
DIAGNOSIS SYSTEM (IPDM E/R) .................126
CONSULT Function (IPDM E/R) ...........................126
ECU DIAGNOSIS INFORMATION ............128
FRONT AIR CONTROL ..................................128
Reference Value .................................................. ..128
ECM, IPDM E/R, BCM .....................................129
List of ECU Reference ...........................................129
WIRING DIAGRAM ....................................130
AIR CONDITIONER CONTROL ......................130
Wiring Diagram .................................................... ..130
BASIC INSPECTION .................................139
DIAGNOSIS AND REPAIR WORKFLOW ......139
Work Flow ............................................................ ..139
OPERATION INSPECTION ............................140
Work Procedure .....................................................140
DTC/CIRCUIT DIAGNOSIS .......................142
MODE DOOR MOTOR ....................................142
Diagnosis Procedure ........................................... ..142
AIR MIX DOOR MOTOR .................................144
Diagnosis Procedure .............................................144
INTAKE DOOR MOTOR .................................146
Diagnosis Procedure .............................................146
BLOWER MOTOR ..........................................148
Diagnosis Procedure .............................................148
Component Inspection (Blower Motor) ..................149
Component Inspection (Front Blower Motor Re-
lay) ....................................................................... ..
149
MAGNET CLUTCH .........................................151
Component Function Check ..................................151
Diagnosis Procedure .............................................151
POWER SUPPLY AND GROUND CIRCUIT
FOR FRONT AIR CONTROL ..........................
152
Description ........................................................... ..152
Component Function Check ..................................152
Diagnosis Procedure .............................................152
SYMPTOM DIAGNOSIS ............................154
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM

HAC-4
HEATER AND AIR CONDITIONING SYSTEM
CONTROL SYMPTOMS ................................. .
154
Symptom Table ................................................... ..154
INSUFFICIENT COOLING ...............................155
Component Function Check ................................ ..155
INSUFFICIENT HEATING ...............................157
Component Function Check ................................ ..157
COMPRESSOR DOES NOT OPERATE .........159
Description ........................................................... ..159
Diagnosis Procedure .............................................159
REMOVAL AND INSTALLATION ..............161
FRONT AIR CONTROL .................................. .161
Removal and Installation ..................................... ..161
IN-VEHICLE SENSOR ......................................162
Removal and Installation .......................................162
REFRIGERANT PRESSURE SENSOR ......... ..163
Removal and Installation .......................................163
DOOR MOTOR ............................................... ..164
Exploded View ..................................................... .164
INTAKE DOOR MOTOR ........................................ .165
INTAKE DOOR MOTOR : Removal and Installa-
tion ....................................................................... .
165
MODE DOOR MOTOR ........................................... .165
MODE DOOR MOTOR : Removal and Installation .165
AIR MIX DOOR MOTOR ........................................ .165
AIR MIX DOOR MOTOR : Removal and Installa-
tion ....................................................................... .
165
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM

PRECAUTIONSHAC-5
< PRECAUTION > [AUTOMATIC AIR CONDITIONER]
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000009951773
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. Information necessary to service t he system safely is included in the SR and SB section of
this Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery and wait at least three mi nutes before performing any service.
Precaution for WorkINFOID:0000000009463086
• When removing or disassembling each component, be ca reful not to damage or deform it. If a component
may be subject to interference, be sure to protect it with a shop cloth.
• When removing (disengaging) components with a screwdriver or similar tool, be sure to wrap the component with a shop cloth or vinyl tape to protect it.
• Protect the removed parts with a shop cloth and prevent them from being dropped.
• Replace a deformed or damaged clip.
• If a part is specified as a non-reusabl e part, always replace it with a new one.
• Be sure to tighten bolts and nuts securely to the specified torque.
• After installation is complete, be sure to check that each part works properly.
• Follow the steps below to clean components:
- Water soluble dirt:
• Dip a soft cloth into lukewarm water, wring the water out of the cloth and wipe the dirty area.
• Then rub with a soft, dry cloth.
-Oily dirt:
• Dip a soft cloth into lukewarm water with mild detergent (concentration: within 2 to 3%) and wipe the dirty area.
• Then dip a cloth into fresh water, wring the water out of the cloth and wipe the detergent off.
• Then rub with a soft, dry cloth.
- Do not use organic solvent such as thinner, benzene, alcohol or gasoline.
- For genuine leather seats, use a genuine leather seat cleaner.
Working with HFC-134a (R-134a)INFOID:0000000009463087
WARNING:
• CFC-12 (R-12) refrigerant and HFC-134a (R-134a) refr igerant are not compatible. If the refrigerants
are mixed compressor failure is likely to occur. Refer to HA-25, "Inspection"
. To determine the purity
of HFC-134a (R-134a) in the vehicle and recovery tank, use Refrigerant Recovery/Recycling Recharg-
ing equipment and Refrigerant Identifier.
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM

HAC-10
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONER]
COMPONENT PARTS
Component Description
INFOID:0000000009463092
1. ECM 2. IPDM E/R 3. BCM (view with combination meter removed)
4. A/C auto amp. (view with A/C switch assembly removed) 5. A/C switch assembly 6. A/C Compressor
7. Sunload sensor 8. Refrigerant pressure sensor (view with front bumper fascia removed)9. Ambient sensor
10. Fuse Block (J/B), Front blower motor relay 11. In-vehicle sensor 12. Accessory relay-2 (view with instru-
ment panel removed)
13. Blower motor (view with front A/C as- sembly removed from vehicle) 14. Intake door motor 15. Mode door motor
16. Air mix door motor LH 17. Air mix door motor RH 18. Intake sensor
ALIIA0599ZZ
Component Description
A/C auto amp. A/C auto amp. controls front automatic air conditioning system by inputting and calculating signals
from each sensor and each switch.
A/C Compressor Vaporized refrigerant is drawn into the A/C compressor from the evaporator, where it is compressed
to a high pressure, high temperature vapor. The hot, compressed vapor is then discharged to the con-
denser.
A/C switch assembly The A/C switch assembly controls the operation of the A/C and heating system based on inputs from
the temperature control knob, the mode switches, the blower control dial, the ambient temperature
sensor, the intake sensor, and inputs received from the ECM across the CAN. Diagnosis of the A/C
switch assembly can be performed using the CONSULT. There is no self-diagnostic feature available.
Air mix door motor LH The air mix door controls the mix of hot or cold air that enters the ventilation system. It is controlled
by the A/C auto amp. based on the position of the temperature dial. The air mix door motor LH re-
ceives position commands from the A/C auto amp. and reports actual door position back via an LCU
(Local Control Unit) installed inside the motor. Commands and responses are sent across the LIN (Lo-
cal Interconnect Network) to each motor simultaneously, with each motor having its own unique ad-
dress, thereby only responding to requests sent to its specific address. The LCU reads the door
position from a Position Balanced Resistor (PBR), also part of the motor, and returns that information
to the A/C auto amp. The LCU switches the polarity of the circuits connected to the DC motor to drive
the motor forward or backward as requested by the A/C auto amp. If the air mix door moves to a po-
sition less than 5% or more than 95% of its expected or allowed positions, the A/C auto amp. will set
a DTC.
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COMPONENT PARTSHAC-11
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONER]
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Air mix door motor RH The air mix door controls the mix of hot or cold air that enters the ventilation system. It is controlled
by the A/C auto amp. based on the position of the temperature dial. The air mix door motor RH re-
ceives position commands from the A/C auto amp. and reports actual door position back via an LCU
(Local Control Unit) installed inside the motor. Commands and responses are sent across the LIN (Lo-
cal Interconnect Network) to each motor simultaneously, with each motor having its own unique ad-
dress, thereby only responding to requests sent to its specific address. The LCU reads the door
position from a Position Balanced Resistor (PBR), also part of the motor, and returns that information
to the A/C auto amp. The LCU switches the polarity of the circuits connected to the DC motor to drive
the motor forward or backward as requested by the A/C auto amp. If the air mix door moves to a po-
sition less than 5% or more than 95% of its expected or allowed positions, the A/C auto amp. will set
a DTC.
Ambient sensor The ambient sensor measures the temperature of the air surrounding the vehicle. The sensor uses a
thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.
BCM The BCM receives the fan ON and A/C ON signals from the A/C auto amp. and sends a compressor
ON request to the ECM.
Blower motor The blower motor varies the speed at which the air flows through the ventilation system.
ECM The ECM sends a compressor ON request to the IPDM E/R based on the status of engine operation
and load as well as refrigerant pressure information. If all the conditions are met for A/C operation,
the ECM transmits the compressor ON request to the IPDM E/R. The ECM shares the refrigerant
pressure sensor signal, engine RPM, and engine coolant temperature with the A/C auto amp. via
CAN communication line.
Front blower motor relay The front blower motor relay controls the flow of current to fuse 17 and 27 in the Fuse Block (J/B).
The relay is connected directly to ground, and is energized when the ignition switch is in the ON or
START position.
Fuse Block (J/B) Located in the passenger compartment, behind the left lower IP, the Fuse Block (J/B) contains the
front blower motor relay and several fuses required for the air conditioner control system.
Intake door motor The intake door motor controls the position of the intake door. Fresh air is allowed to enter the cabin
in one position, and recirculated inside air is allowed to enter in the other position. At times the A/C
auto amp. may command partial fresh or recirculation based on evaporator or coolant temperatures.
The intake door motor receives position commands from the A/C auto amp. and reports actual door
position back via an LCU (Local Control Unit) installed inside the motor. Commands and responses
are sent across the LIN (Local Interconnect Network) to each motor simultaneously, with each motor
having its own unique address, thereby only responding to requests sent to its specific address. The
LCU reads the door position from a Position Balanced Resistor (PBR), also part of the motor, and re-
turns that information to the A/C auto amp. The LCU switches the polarity of the circuits connected to
the DC motor to drive the motor forward or backward as requested by the A/C auto amp. If the recir-
culation door moves to a position less than 5% or more than 95% of its expected or allowed positions,
the A/C auto amp. will set a DTC.
Intake sensor The intake sensor measures the temperature of the front evaporator fins. The sensor uses a ther-
mistor which is sensitive to the change in temperature. The electrical resistance of the thermistor de-
creases as temperature increases.
In-vehicle sensor In-vehicle sensor measures temperature of intake air that flows through aspirator to passenger room.
The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resis-
tance of the thermistor decreases as temperature increases.
IPDM E/R Refer to PCS-6, "RELAY CONTROL SYSTEM : System Description"
.
Mode door motor The mode door controls the direction the conditioned air passes through the ventilation system.
Through a series of levers and gears, the mode door controls the defrost door, the foot door, and the
vent door. There are 5 preset positions: VENT, B/L, FOOT, D/F, and DEF. The FOOT position can be
set to allow some airflow through to the defroster vent, or to completely block the defroster vent using
the CONSULT. The mode door motor receives position commands from the A/C auto amp. and re-
ports actual door position back via an LCU (Local Control Unit) installed inside the motor. Commands
and responses are sent across the LIN (Local Interconnect Network) to each motor simultaneously,
with each motor having its own unique address, thereby only responding to requests sent to its spe-
cific address. The LCU reads the door position from a Position Balanced Resistor (PBR), also part of
the motor, and returns that information to the A/C auto amp. The LCU switches the polarity of the cir-
cuits connected to the DC motor to drive the motor forward or backward as requested by the A/C auto
amp. The mode door has 5 expected positions and, therefore, can set up to 5 DTCs if the expected
position is not reported back to the A/C auto amp.
Component Description
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM

HAC-12
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONER]
COMPONENT PARTS
Refrigerant pressure sensorRefer to
EC-36, "Refrigerant Pressure Sensor" for QR25DE and EC-562, "Refrigerant Pressure Sen-
sor" for VQ35DE.
Sunload sensor Sunload sensor measures sunload amount. This sensor is a dual system so that sunload for driver
side and passenger side are measured separately. This sensor converts sunload amount to voltage
signal by photodiode and transmits to A/C auto amp.
Component Description
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM

HAC-14
< SYSTEM DESCRIPTION >[AUTOMATIC AIR CONDITIONER]
SYSTEM
-
HAC-16, "Compressor Control"
-HAC-17, "Door Control"
-HAC-20, "Temperature Control"
- Correction for input value of each sensor
Ambient sensor (setting temperature correction)• A/C auto amp. controls passenger r oom temperature so that the optimum level always matches the temper-
ature level that the passenger may feel. Correction is appl ied to the target temperature that is set using tem-
perature control dial, according to ambient temperature detected by ambient sensor.
In-vehicle sensor [in-vehicle temperature correction]• Passenger room temperature detected by in-vehicle s ensor is corrected for each front air conditioning con-
trol (driver side and passenger side).
Intake sensor (intake temperature correction)• A/C auto amp. performs correction to change recogniti on intake temperature of A/C auto amp. quickly when
difference is large between recognition intake temperat ure and intake temperature detected by intake tem-
perature sensor. The correction is performed to change recognition intake temperature slowly when differ-
ence is small.
Sunload sensor (sunload amount correction)
• Sunload amount detected by sunload sensor is corrected for each air conditioning control.
• A/C auto amp. performs correction to change recogni tion sunload amount of A/C auto amp. slowly when
sunload amount changes quickly, for example when entering or exiting a tunnel.
Control by ECM- Cooling fan control Refer to EC-59, "COOLING FAN CONTROL : System De scription (with automatic air conditioner)"
(QR25DE) or EC-575, "COOLING FAN CONTRO L : System Description" (VQ35DE).
- Air conditioning cut control
Refer to EC-59, "COOLING FAN CONTROL : System De scription (with automatic air conditioner)"
(QR25DE) or EC-573, "AIR CONDITIONING CUT CONTROL : System Description" (VQ35DE).
Control by IPDM E/R- Relay control
Refer to PCS-6, "RELAY CONTROL SYSTEM : System Description"
.
- Cooling fan control
Refer to EC-59, "COOLING FAN CONTROL : System De scription (with automatic air conditioner)"
(QR25DE) or EC-575, "COOLING FAN CONTRO L : System Description" (VQ35DE).
Control by BCM- Relay control
Refer to BCS-7, "BODY CONTROL SYST EM : System Description"
.
Air Flow ControlINFOID:0000000009463095
DESCRIPTION
• A/C auto amp. changes duty ratio of blower motor dr ive signal and controls air flow continuously. When air
flow is increased, duty ratio of blower motor contro l signal gradually increases to prevent a sudden increase
in air flow.
• In addition to manual control and automatic control, air fl ow control consists of starting fan speed control, low
coolant temperature starting control, high in-vehicl e temperature starting control and fan speed control at
door motor operation
AUTOMATIC AIR FLOW CONTROL
• A/C auto amp. decides target air flow depending on target air mix door opening angle.
• A/C auto amp. changes duty ratio of blower motor c ontrol signal and controls the air flow continuously so
that air flow matches the target air flow.
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SYSTEMHAC-15
< SYSTEM DESCRIPTION > [AUTOMATIC AIR CONDITIONER]
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• When air outlet is VENT or B/L, the minimum air flow is changed depending on sunload.
STARTING AIR FLOW CONTROL
• When blower motor is activated, A/C auto amp. graduallyincreases duty ratio of blower motor control signal to prevent a
sudden increase in discharge air flow.
• It takes approximately 8 seconds for air flow to reach HI from LOW.
LOW COOLANT TEMPERATURE STARTING CONTROL
If the engine coolant temperature is 56 °C (133 °F) or less, to prevent
a cold discharged air flow, A/C auto amp. suspends blower motor
activation for a maximum of 150 seconds depending on target air
mix door opening angle. After this, blower motor control signal is
increased gradually, and blower motor is activated.
HIGH IN-VEHICLE TEMPERATURE STARTING CONTROL
When front evaporator fin temperature is high [intake sensor value is 35°C (95 °F) or more], to prevent a hot
discharged air flow, A/C auto amp. suspends blower moto r activation for approximately 3 seconds so that front
evaporator is cooled by refrigerant.
FAN SPEED CONTROL AT DOOR MOTOR OPERATION
When mode door motor is activated while air flow is more than the specified value, A/C auto amp. reduces fan
speed temporarily so that mode door moves smoothly.
Air Inlet ControlINFOID:0000000009463096
The intake door is automatically controlled by the temperature set-
ting, ambient temperature, in-vehicle temperature, intake tempera-
ture, amount of sunload and ON/OFF operation of the compressor.
Intake door automatic control selects FRE, 20% FRE, or REC
depending on a target air mix door opening angle, based on in-vehi-
cle temperature, ambient temperature, and sunload.
JMIIA0735GB
JMIIA0736GB
JMIIA0737GB
JMIIA0732GB
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM