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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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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SYSTEM
HAC-121
< SYSTEM DESCRIPTION > [MANUAL AIR CONDITIONER]
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Temperature ControlINFOID:0000000009463201
• When the ignition switch is in the ON position, the cu stomer uses the front air control temperature control
dial to set the desired temperature.
• The front air control calculates the target front air mix door opening angle depending on the selected temper-
ature, intake temperature sensor, engine coolant temperature and rpm, and ambient temperature.
• Front air mix door is controlled depending on the comparison of current front air mix door opening angle and target front air mix door opening angle.
• Regardless of ambient temperature, the front air mix door is fixed at the fully cold position when the temper-
ature control dial is set at the full cold position and fi xed at the fully hot position when the temperature control
dial is set at the full hot position.
VENT MODE ( )
OUTLET VENT
ASST CTR
DR RR
ASST DR
AIR FLOW DISTRIBUTION RATIO (%) 22 22 22 22 12
B/L MODE ( )
OUTLET VENT FOOT
ASST CTR
DR RR Fr ASST Fr DR Rr ASST Rr DR
ASST DR
AIR FLOW DISTRIBUTION RATIO (%) 11 11 11 11 1 7 1 4 . 5 1 4 . 5 5 5
D/F1 MODE ( )
OUTLET VENT FOOT DEF
ASST CTR
DR RR Fr
ASST Fr DR
Rr
ASST Rr DR Fr Side
ASST DR
AIR FLOW DISTRIBUTION RATIO(%) 5 0 0 5 17 18 18 7 7 18 5
D/F2 MODE ( )
OUTLET VENT FOOT DEF
ASST CTR
DR RR Fr
ASST Fr DR
Rr
ASST Rr DR Fr Side
ASST DR
AIR FLOW DISTRIBUTION RATIO(%) 5 0 0 5 17 14 14 6.5 6.5 25 7
DEF MODE ( )
OUTLET VENT FOOT DEF
ASST CTR
DR RR Fr
ASST Fr DR
Rr
ASST Rr DR Fr Side
ASST DR
AIR FLOW DISTRIBUTION RATIO(%) 5 0 0 5 14 0 0 0 0 60 16
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INSUFFICIENT HEATINGHAC-157
< SYMPTOM DIAGNOSIS > [MANUAL AIR CONDITIONER]
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INSUFFICIENT HEATING
Component Function CheckINFOID:0000000009463224
SYMPTOM: Insufficient heating
INSPECTION FLOW
1. CONFIRM SYMPTOM BY PERFORMING OP ERATION CHECK - TEMPERATURE INCREASE
1. Turn temperature control dial clockwise to maximum heat.
2. Check for hot air at discharge air outlets.
Can a symptom be duplicated?
YES >> GO TO 3
NO >> GO TO 2
2. CHECK FOR ANY SYMPTOMS
Perform a complete operational check and check for any symptoms. Refer to HAC-140, "Work Procedure"
.
Does another symptom exist?
YES >> Refer to HAC-154, "Symptom Table".
NO >> System OK.
3. CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4
4. CHECK ENGINE COOLING SYSTEM
1. Check for proper engine coolant level. Refer to CO-11, "System Inspection"
(QR25DE) or CO-35, "System
Inspection" (VQ35DE).
2. Check hoses for leaks or kinks.
3. Check radiator cap. Refer to CO-11, "System Inspection"
(QR25DE) or CO-35, "System Inspection"
(VQ35DE).
4. Check for air in cooling system.
>> GO TO 5
5. CHECK AIR MIX DOOR MOTOR OPERATION
Check and verify air mix door mechanism for smooth operation.
Does air mix door operate correctly?
YES >> GO TO 6
NO >> Check the air mix door motor circuit. Refer to HAC-144, "Diagnosis Procedure"
.
6. CHECK AIR DUCTS
Check for disconnected or leaking air ducts.
Is the inspection result normal?
YES >> GO TO 7
NO >> Repair all disconnected or leaking air ducts.
7. CHECK HEATER HOSE TEMPERATURES
1. Start engine and warm it up to normal operating temperature.
2. Touch both the inlet and outlet heater hoses. The inlet hose should be hot and the outlet hose should be
warm.
Is the inspection result normal?
YES >> GO TO 8
NO >> Both hoses warm: GO TO 9
8. CHECK ENGINE COOLANT SYSTEM
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HAC-158
< SYMPTOM DIAGNOSIS >[MANUAL AIR CONDITIONER]
INSUFFICIENT HEATING
Check thermostat operation. Refer to
CO-22, "Removal and Installation" (QR25DE) or CO-49, "Removal and
Installation" (VQ35DE).
Is the inspection result normal?
YES >> System OK.
NO >> Repair or replace as necessary.
9. CHECK HEATER HOSES
Check heater hoses for proper installation.
Is the inspection result normal?
YES >> System OK.
NO >> 1. Back flush heater core. 2. Drain the water from the system.
3. Refill system with new engine coolant. Refer to CO-12, "Changing Engine Coolant"
(QR25DE) or CO-36, "Changing Engine Coolant" (VQ35DE).
4. To retest GO TO 10
10. CHECK HEATER HOSE TEMPERATURES
1. Start engine and warm up to normal operating temperature.
2. Touch both the inlet and outlet heater hoses. The inlet hose should be hot and the outlet hose should be
warm
Is the inspection result normal?
YES >> System OK.
NO >> Replace heater core. Refer to HA-42, "HEATER CORE : Removal and Installation"
.
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LAN-32
< SYSTEM DESCRIPTION >[CAN]
SYSTEM
CAN COMMUNICATION SYSTEM : CA N Communication Signal Chart
INFOID:0000000009461413
Refer to LAN-17, "How to Use CAN Communication Signal Chart" for how to use CAN communication signal
chart.
NOTE:
Refer to LAN-23, "Abbreviation List"
for the abbreviations of the connecting units.
T: Transmit R: Receive
Warning systems switch 7 inch color display NAVI switches
Automatic temperature control dial
With driver assistance system With Navigation system With auto A/C
AWMIA1453ZZ
Signal nameECM
EPS
IPDM-E TCM
M&A
STRG AV
AV M
HVAC ABS
BCM
A/C compressor request signal T R R
Accelerator pedal position signal T R R R
ASCD operation signal T R
ASCD status signal T R
Closed throttle position signal T R
Cooling fan speed request signal T R R
Engine coolant temperature signal T R R R R R
Engine and CVT integrated control
signal TR
RT
Engine speed signal T RR RRRR
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LU-4
< PRECAUTION >[QR25DE]
PRECAUTIONS
4. Apply the liquid gasket using suitable tool without breaks to the
specified location.
• If there is a groove for the liquid gasket application, apply the
liquid gasket to the groove.
• As for the bolt holes, normally apply the liquid gasket inside the holes. If specified, it should be applied outside the holes.
Make sure to read the text of this manual.
• Within five minutes of the liquid gasket application, install the mating component.
• If the liquid gasket protrudes, wipe it off immediately.
• Do not retighten after the installation.
• After 30 minutes or more have passed from the installation, fill the engine with the specified oil and coolant. Refer to MA-11,
"FOR USA AND CANADA : Fluids and Lubricants".
CAUTION:
If there are more specific instruct ions in the procedures contained in this manual concerning liquid
gasket applicatio n, observe them.
EMA0622D
SEM159F
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ENGINE OILLU-9
< PERIODIC MAINTENANCE > [QR25DE]
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PERIODIC MAINTENANCE
ENGINE OIL
InspectionINFOID:0000000009461028
OIL LEVEL
• Before starting the engine, check the oil level. If t
he engine is already started, stop it and allow 10 minutes
before checking.
• Check that the oil level is within the range (A) on the oil level
gauge.
• If it is out of range, add oil as necessary.
ENGINE OIL APPEARANCE
• Check engine oil for white milky appearance or excessive contamination.
• If engine oil becomes milky, it is highly probable t hat it is contaminated with engine coolant. Repair or
replace damaged parts.
OIL LEAKAGE
Check for oil leakage around the following areas:
•Oil pan
• Oil pan drain plug
• Oil pressure switch
• Oil filter
• Oil cooler
• Valve timing control cover and valve timing control solenoid valve
• Front cover
• Mating surface between cylinder block and cylinder head
• Mating surface between cylinder head and rocker cover
• Crankshaft oil seal (front and rear)
OIL PRESSURE CHECK
WARNING:
• Be careful not to burn yoursel f, as engine oil may be hot.
• Put the CVT shift selector in the Park "P" position.
1. Check engine oil level. Refer to OIL LEVEL.
2. Remove fender protector side cover (RH). Refer to EXT-26, "FENDER PROTECTOR : Exploded View"
.
3. Disconnect oil pressure switch harness connector at oil pressure switch. Remove oil pressure switch and install Tools.
CAUTION:
Do not drop or shock oil pressure switch.
4. Start engine and warm it up to normal operating temperature.
5. Check oil pressure with engine running under no-load, using Tool. NOTE:
JPBIA1497ZZ
Tool numbers : ST25051001 (J-25695-1)
: ST25052000 (J-25695-2)
WBIA0571E
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