Its control NISSAN TEANA 2014 Service Manual

COMPONENT PARTSHAC-115
< SYSTEM DESCRIPTION > [MANUAL AIR CONDITIONER]
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Component DescriptionINFOID:0000000009463193
7. Refrigerant pressure sensor (view with front bumper fascia removed) 8. Blower motor (view with front air con-
ditioning assembly removed from ve-
hicle) 9. Intake door motor
10. Mode door motor 11. Air mix door motor
Component Description
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.
Air mix door motor The air mix door controls the mix of hot or cold air that enters the ventilation system. It is controlled
by the front air control based on the position of the temperature dial. The air mix door motor receives
position commands from the front air control 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 In-
terconnect 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 returns that information to the front
air control. The LCU switches the polarity of the circuits connected to the DC motor to drive the motor
forward or backward as requested by the front air control.
BCM The BCM receives the fan ON and A/C ON signals from the front air control 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 front air control via
CAN communication line.
Front air control The front air control 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, and inputs received from the
ECM and combination meter across the CAN.
Front blower motor relay The front blower motor relay controls the flow of current to fuses 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 front
air control may command partial fresh or recirculation based on evaporator or coolant temperatures.
The intake door motor receives position commands from the front air control 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 front air control. The LCU switches the polarity of the circuits connected
to the DC motor to drive the motor forward or backward as requested by the front air control.
IPDM E/R Refer to PCS-6, "RELAY CONTROL SYSTEM : System Description"
.
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HAC-116
< SYSTEM DESCRIPTION >[MANUAL AIR CONDITIONER]
COMPONENT PARTS
Mode door motorThe 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 front air control 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 front air control. The LCU switches the polarity of the
circuits connected to the DC motor to drive the motor forward or backward as requested by the front
air control.
Refrigerant pressure sensor Refer to
EC-36, "Refrigerant Pressure Sensor"
for QR25DE and EC-562, "Refrigerant Pressure Sen-
sor" for VQ35DE.
Component Description
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SYSTEM
HAC-119
< SYSTEM DESCRIPTION > [MANUAL AIR CONDITIONER]
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2. The blower speed dial is turned completely counterclockwise to the OFF position.
3. The A/C switch is manually turned OFF.
In other words, the compressor ON request cannot be turned off in D/F or DEF modes.
REFRIGERANT PRESSURE PROTECTION
The refrigerant system is protected against excessively high- or low-pressures by the refrigerant pressure sen-
sor, located on the liquid tank on the condenser. The refr igerant pressure sensor detects the pressure inside
the refrigerant line and sends a voltage signal to the EC M. If the system pressure rises above or falls below
the following values, the ECM requests the IPDM E/ R to de-energize the A/C relay and disengage the com-
pressor.
• 3.12 MPa (31.82 kg/cm
2, 452.4 psi) or more (When the engine speed is less than 1,500 rpm)
• 2.74 MPa (27.95 kg/cm
2, 397.3 psi) or more (When the engine speed is 1,500 rpm or more)
• 0.14 MPa (1.43 kg/cm
2, 20.3 psi) or less
PRESSURE RELIEF VALVE
The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system incr eases to an abnormal level [more than 2,990 kPa (30.5 kg/
cm
2, 433.6 psi)], the release port on the pressure relief valve automatically opens and releases refrigerant into
the atmosphere.
COMPRESSOR OIL CIRCULATION CONTROL
When the engine starts while the engine coolant temperature is 56 °C (133 °F) or less, ECM activates the com-
pressor for approximately 6 seconds and circulates the compressor lubricant once.
OPERATING RATE CONTROL
When the set temperature is other than fully cold or the air outlet is “VENT”, “B/L” or “FOOT”, the front air con-
trol controls the compressor activation depending on ambient temperature.
Door ControlINFOID:0000000009463200
DOOR MOTOR CONTROL
• A Local Control Unit (LCU) is built into each door motor and detects the door position by using a Position
Balanced Resistor (PBR).
• Each door motor LCU has a unique address. The front air control communicates with the door motor LCUs by using each door’s unique communication address. The front air control sends requested door position
commands to each door motor LCU via a Local Interconnect Network (LIN) communication line. Each door
motor’s LCU receives the command and sends back a door position feedback signal.
• Each LCU controls each door to the appropriate posit ion depending on the control signal from the front air
control. When the door movement is complete, the LCU transmits a signal to the front air control indicating
that the door movement is complete.
SWITCHES AND THEIR CONTROL FUNCTION
ALIIA0607GB
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SYSTEMLAN-9
< SYSTEM DESCRIPTION > [CAN FUNDAMENTAL]
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SYSTEM DESCRIPTION
SYSTEM
CAN COMMUNICATION SYSTEM
CAN COMMUNICATION SYSTEM : System DescriptionINFOID:0000000009461393
CAN (Controller Area Network) is a serial communication li
ne for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
DIAG ON CAN
DIAG ON CAN : System DescriptionINFOID:0000000009461394
SYSTEM DIAGRAM
JSMIA0526GB
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TROUBLE DIAGNOSISLAN-11
< SYSTEM DESCRIPTION > [CAN FUNDAMENTAL]
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TROUBLE DIAGNOSIS
Component DescriptionINFOID:0000000009461395
Condition of Error DetectionINFOID:0000000009461396
DTC (e.g. U1000 and U1001) of CAN communication is
indicated on SELF-DIAG RESULTS on CONSULT if a
CAN communication signal is not transmitted or received between units for 2 seconds or more.
CAN COMMUNICATION SYSTEM ERROR
• CAN communication line open (CAN-H, CAN-L, or both)
• CAN communication line short (ground, betw een CAN communication lines, other harnesses)
• Error of CAN communication control circuit of the unit connected to CAN communication line
WHEN DTC OF CAN COMMUNICATION IS I NDICATED EVEN THOUGH CAN COMMUNICATION
SYSTEM IS NORMAL
• Removal/installation of parts: Error may be detec ted when removing and installing CAN communication unit
and related parts while turning the ignition switch ON. (A DTC except for CAN communication may be
detected.)
• Fuse blown out (removed): CAN communication of the unit may cease.
• Voltage drop: Error may be detected if voltage drops due to discharged battery when turning the ignition switch ON (Depending on the control unit which carries out CAN communication).
• Error may be detected if the power supply circuit of the control unit, which carries out CAN communication,
malfunctions (Depending on the control unit which carries out CAN communication).
• Error may be detected if reprogramming is not completed normally.
NOTE:
CAN communication system is normal if DTC of CAN communication is indicated on SELF-DIAG RESULTS of
CONSULT under the above conditions. Erase the memory of the self-diagnosis of each control unit.
JSMIA0527GB
Component Description
Main line CAN communication line between splices
Branch line CAN communication line between splice and a control unit
Splice A point connecting a branch line with a main line
Termination circuit Circuit connected across the CAN communication system. (Resistor)
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< SYSTEM DESCRIPTION >[CAN FUNDAMENTAL]
TROUBLE DIAGNOSIS
Symptom When Error Occurs in CAN Communication System
INFOID:0000000009461397
In CAN communication system, multiple control units mutually transmit and receive signals. Each control unit
cannot transmit and receive signals if any error occurs on CAN communication line. Under this condition, mul-
tiple control units related to the root cause malfunction or go into fail-safe mode.
ERROR EXAMPLE
NOTE:
Each vehicle differs in symptom of each control unit under fail-safe mode and CAN communication line wiring.
Example: Main Line Between Data Link Connector and ABS Actuator and Electric Un it (Control Unit) Open Circuit
JSMIA0442GB
Unit name Major symptom
ECM Engine torque limiting is affected, and shift harshness increases.
BCM • Reverse warning buzzer does not sound.
• The front wiper moves under continuous operation mode even though the front wip- er switch being in the intermittent position.
EPS control unit The steeri ng effort increases.
Combination meter • The shift position indicator and OD OFF indicator turn OFF.
• The speedometer is inoperative.
• The odo/trip meter stops.
ABS actuator and electric unit (control unit) Normal operation.
TCM No impact on operation.
IPDM E/R When the ignition switch is ON,
• The headlamps (Lo) turn ON.
• The cooling fan continues to rotate.
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< SYSTEM DESCRIPTION > [CAN FUNDAMENTAL]
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Example: TCM Branch Line Open Circuit
NOTE:
The model (all control units on CAN communication system are Diag on CAN) cannot perform CAN diagnosis
with CONSULT if the following error occurs. The error is judged by the symptom.
Example: Data Link Connector Branch Line Open Circuit
JSMIA0443GB
Unit name Major symptom
ECM Engine torque limiting is affected, and shift harshness increases.
BCM Reverse warning buzzer does not sound.
EPS control unit Normal operation.
Combination meter • Shift position indicator and O/D OFF indicator turn OFF.
• Warning lamps turn ON.
ABS actuator and electric unit (control unit) Normal operation.
TCM No impact on operation.
IPDM E/R Normal operation.
Error Difference of symptom
Data link connector branch line open circuit Normal operation.
CAN-H, CAN-L harness short-circuit Most of the control units which are connected to the CAN commu-
nication system enter fail-safe mode or are deactivated.
JSMIA0444GB
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< SYSTEM DESCRIPTION > [CAN FUNDAMENTAL]
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• Response to the system call
• Control unit diagnosis information
• Self-diagnosis
• CAN diagnostic support monitor
Self-DiagnosisINFOID:0000000009461399
If communication signals cannot be transmitted or rece ived among control units communicating via CAN com-
munication line, CAN communication-related DTC is displayed on the CONSULT “Self Diagnostic Result”
screen.
NOTE:
The following table shows examples of CAN communicati on-related DTC. For other DTC, refer to the applica-
ble sections.
CAN Diagnostic Support MonitorINFOID:0000000009461400
MONITOR ITEM (CONSULT)
Example: CAN DIAG SUPPORT MNTR indication
Without PAST
DTC Self-diagnosis item
(CONSULT indication) DTC detection condition Inspection/Action
U1000 CAN COMM CIRCUIT ECM
When ECM is not transmitting or receiving CAN
communication signal of OBD (emission-relat-
ed diagnosis) for 2 seconds or more.
Start the inspection. Re-
fer to the applicable sec-
tion of the indicated
control unit.
Except
for ECM When a control unit (except for ECM) is not
transmitting or receiving CAN communication
signal for 2 seconds or more.
U1001 CAN COMM CIRCUIT When ECM is not transmitting or receiving CAN communi-
cation signal other than OBD (emission-related diagnosis)
for 2 seconds or more.
U1002 SYSTEM COMM When a control unit is not transmitting or receiving CAN
communication signal for 2 seconds or less.
U1010 CONTROL UNIT(CAN) When an error is detected during the initial diagnosis for
CAN controller of each control unit. Replace the control unit
indicating “U1010”.
JSMIA0964GB
Item PRESENT Description
Initial diagnosis OK Normal at present
NG Control unit e rror (Except for some control units)
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< SYSTEM DESCRIPTION > [CAN FUNDAMENTAL]
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How to Use CAN Communication Signal ChartINFOID:0000000009461401
The CAN communication signal chart lists the signals trans
mitted/received among control units. It is useful for
detecting the root cause by finding a signal related to the symptom, and by checking transmission and recep-
tion unit.
JSMIA0446GB
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< BASIC INSPECTION >[CAN FUNDAMENTAL]
DIAGNOSIS AND REPAIR WORKFLOW
BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Trouble Diagnosis Flow ChartINFOID:0000000009461402
Trouble Diagnosis ProcedureINFOID:0000000009461403
INTERVIEW WITH CUSTOMER
Interview with the customer is important to detect
the root cause of CAN communication system errors and to
understand vehicle condition and symptoms for proper trouble diagnosis.
Points in interview• What: Parts name, system name
• When: Date, Frequency
• Where: Road condition, Place
• In what condition: Driving condition/environment
• Result: Symptom
Notes for checking error symptoms:• Check normal units as well as error symptoms.
- Example: Circuit between ECM and the combination me ter is judged normal if the customer indicates
tachometer functions normally.
• When a CAN communication system error is present, multiple control units may malfunction or go into fail-
safe mode.
JSMIA0528GB
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