HEATER & COOLING UNIT ASSEMBLYVTL-17
< ON-VEHICLE REPAIR >
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1. Move the two front seats to the rear most position on the seat track.
2. Disconnect the battery negative terminal and battery positive terminal.
3. Discharge the refrigerant from the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
4. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
5. Disconnect the front heater hoses from the front heater core.
6. Disconnect the high/low pressure pipes from the front expansion valve.
7. Remove the instrument panel and console panel. Refer to IP-12, "
Removal and Installation".
8. Remove the steering column. Refer to ST-20, "
Removal and Installation".
9. Disconnect the instrument panel wire harness at t he RH and LH in-line connector brackets, and the fuse
block (J/B) electrical connectors. Refer to PG-9, "
Wiring Diagram — Battery Power Supply —".
10. Disconnect the steering member from each side of the vehicle body.
11. Remove the front heater and cooling unit assembly with it attached to the steering member, from the vehi- cle.
CAUTION:
Use care not to damage the seats and interior trim panels when removing the front heater and
cooling unit assembly with it at tached to the steering member.
12. Remove the front heater and cooling uni t assembly from the steering member.
Installation
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply com-
pressor oil to it when installing it.
• After charging the refrigerant, check for leaks.
NOTE:
• Fill the engine cooling system with the specified coolant mixture. Refer to CO-11, "
Changing Engine Cool-
ant".
• Recharge the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
REAR HEATER AND COOLING UNIT ASSEMBLY
Removal
1. Discharge the refrigerant from the A/C system. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
3. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
4. Disconnect the rear heater core hoses from the rear heater core.
5. Disconnect the rear A/C pipes from the rear expansion valve.
6. Disconnect the following electrical connectors: • Rear blower motor
• Rear variable blower control
• Rear air mix door motor
7. Disconnect the ducts from the rear heater and cooling unit assembly.
8. Remove the rear heater and cooling unit assembly.
Installation
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply com- pressor oil to it when installing it.
• After charging the refrigerant, check for leaks.
NOTE:
• Fill the engine cooling system with the specified coolant mixture. Refer to CO-11, "
Changing Engine Cool-
ant".
• Recharge the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
Revision: March 2010 2008 QX56
WCS-2
WARNING CHIME SYSTEM .............................24
Wiring Diagram .................................................... ...24
ECU DIAGNOSIS ..................................... ...29
COMBINATION METER ................................. ...29
Reference Value .................................................. ...29
Wiring Diagram .......................................................31
Fail Safe .................................................................48
DTC Index ..............................................................49
BCM (BODY CONTROL MODULE) ..................51
Reference Value .................................................. ...51
Terminal Layout ......................................................53
Physical Values ......................................................53
Wiring Diagram .......................................................59
Fail Safe .................................................................62
DTC Inspection Priority Chart ..............................63
DTC Index ........................................................... ...63
SYMPTOM DIAGNOSIS .............................65
THE LIGHT REMINDER WARNING DOES
NOT SOUND ................................................... ...
65
Description ........................................................... ...65
Diagnosis Procedure ...............................................65
THE SEAT BELT WARNING CONTINUES
SOUNDING, OR DOES NOT SOUND ...............
66
Description ........................................................... ...66
Diagnosis Procedure ...............................................66
THE KEY WARNING DOES NOT SOUND .......67
Description ........................................................... ...67
Diagnosis Procedure ...............................................67
PRECAUTION ............................................68
PRECAUTIONS .............................................. ...68
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ...
68
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ..................................
68
Revision: March 2010 2008 QX56
WCS-12
< FUNCTION DIAGNOSIS >
DIAGNOSIS SYSTEM (METER)
DIAGNOSIS SYSTEM (METER)
Diagnosis DescriptionINFOID:0000000004872660
SELF-DIAGNOSIS MODE
The following items can be checked during Combination Meter Self-Diagnosis Mode.
• Gauge sweep and present gauge values.
• Illuminates all odometer/trip meters and A/T indicator segments.
• Illuminates all micro controlled lamps/LEDs regardless of switch position.
• Displays estimated present battery voltage.
• Displays seat belt buckle switch LH status.
OPERATION PROCEDURE
NOTE:
• Once entered, combination meter self-diagnosis mode will function with the ignition switch in ON or START.
Combination meter self-diagnosis mode will exit upon turning the ignition switch to OFF or ACC.
• If the diagnosis function is activated with trip A displa yed, the mileage on trip A is reset to 0000.0. (Trip B
operates the same way.)
To initiate combination meter self-diagnosis mode, refer to the following procedure.
1. Turn the ignition switch ON, while pressing the odometer/trip meter switch for 5 - 8 \
seconds. When the diagnosis function is activated, the odometer/trip meter will display tESt.
NOTE:
Check combination meter power supply and ground circuit when self-diagnosis mode of combination meter
does not start. Refer to MWI-30, "
COMBINATION METER : Diagnosis Procedure". Replace combination
meter if normal. Refer to MWI-76, "
Removal and Installation".
COMBINATION METER SELF-DIAGNOSIS MODE FUNCTIONS
To interpret combination meter self-diagnosis mode functions, refer to the following table.
EventOdometer Display Description of Test/Data Notes:
Odometer/trip meter A/B
switch held from 5 to 8
seconds (or until re-
leased) tESt
Initiating self-diagnosis mode
Switch released GAGE Performs sweep of all
gauges, then displays
present gauge values.Gauges sweep within 10 seconds
Switch pressed (All segments illuminated) Lights all LCD segments.
Compare with picture.
Switch pressed bulbIlluminates all micro-con-
trolled lamps/LEDs. Part may not be configured for all
lamps (functions) th
at turn on dur-
ing test. This is normal.
Switch pressed r XXXX, FAIL Return to normal opera-
tion of all lamps/LEDs and
displays “r XXXX”.If a malfunction exists, “FAIL” will
flash.
Switch pressed nrXXXX Displays Hex ROM rev as
stored in NVM.
Switch pressed EE XX, FAIL Displays “EE XX”.If a malfunction exists, “FAIL” will
flash.
Switch pressed dtXXXX Hex coding of final manu-
facturing test date.
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Revision: March 2010
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WCS
DIAGNOSIS SYSTEM (METER)WCS-13
< FUNCTION DIAGNOSIS >
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CONSULT-III Function (METER/M&A)INFOID:0000000004872661
CONSULT-III can display each diagnostic item us ing the diagnostic test modes shown following.
SELF-DIAG RESULTS
Display Item List
Refer to MWI-62, "DTC Index".
DATA MONITOR
Display Item List
Switch pressed
(3 times) Sc1 XX through Epr XXDisplays 8 bit software
configuration value in Hex
format
Switch pressed 1nF XXDisplays 8-bit market info
value in Hex format. $31 = USA
$2A = Canada
Switch pressed
(3 times) cYL XX through tF N/A
Switch pressed XXXXX “Corrected” speed value
in hundredths of MPH.
Gauge indication may be
slightly higher. This is nor-
mal.Will display “-----” if message is not
received. Will display “99999” if
data received is invalid.
Switch pressed XXXXX “Corrected” speed value
in hundredths of KPH.
Gauge indication may be
slightly different. This is
normal.Will display “-----” if message is not
received. Will display “99999” if
data received is invalid.
Switch pressed t XXXX Tachometer value in
RPM. Gauge indication
may be higher at higher
RPM. This is normal.Will display “-----” if message is not
received.
Switch pressed F1XXXX Present fuel level A/D in-
put. This input represents
fuel sender input.000-009 = Short circuit
010-254 = Normal range
255 = Open circuit
Switch pressed F2XXX Present FLPS.010-254 = Normal range
Switch pressed XXXC Last temperature gauge
input value in degrees C.
Temperature gauge indi-
cates present tempera-
ture per indication
standard.Will display “---”C if
message is not
received.
Will display “999” if data received
is invalid.
High = 130 deg C
Normal = 70 - 105 deg C
Low = less than 50 deg C
Switch pressed BAtXX.X Estimated present battery
voltage.
Switch pressed rES -X Seat belt buckle switch LH
status.1= Buckled
0 = Unbuckled
Switch pressed
(32 times) PA -XX through PA1-XX N/A
Switch pressed GAGE Return to beginning of self-diagno-
sis cycle.
Event
Odometer Display Description of Test/Data Notes:
METER/M&A diagnosis mode Description
SELF-DIAG RESULTS Displays combination meter self-diagnosis results. DATA MONITOR Displays combination meter input/output data in real time.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
Revision: March 2010 2008 QX56
WCS
POWER SUPPLY AND GROUND CIRCUITWCS-17
< COMPONENT DIAGNOSIS >
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COMPONENT DIAGNOSIS
POWER SUPPLY AND GROUND CIRCUIT
COMBINATION METER
COMBINATION METER : Diagnosis ProcedureINFOID:0000000004873060
1.CHECK FUSES
Check for blown combination meter fuses.
Is the inspection result normal?
YES >> GO TO 2
NO >> If fuse is blown, be sure to eliminate cause of malfunction before installing new fuse.
2.POWER SUPPLY CIRCUIT CHECK
1. Disconnect combination meter connector M24.
2. Check voltage between combination meter harness connector M24 terminals 21, 37, 40 and ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Check harness for open between combination meter and fuse.
3.GROUND CIRCUIT CHECK
1. Turn ignition switch OFF.
2. Disconnect combination meter connector M23.
3. Check continuity between combination meter harness connector M23 terminal 47, 52 and ground, and connector M24 terminal 20
and ground.
Is the inspection result normal?
YES >> Inspection End.
NO >> Check ground harness.
Unit Power source Fuse No.
Combination meter Battery 19
Ignition switch ON or START 14
Ignition switch ACC or ON 4
TerminalsIgnition switch position
(+) (–) OFF ACC ON START
Connector Terminal
M24 21
Ground 0V 0V
Battery
voltage Battery
voltage
37 0VBattery
voltage Battery
voltage 0V
40 Battery
voltage Battery
voltage Battery
voltage Battery
voltage
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Te r m i n a l s
Continuity
(+)
(–)
Connector Terminal
A: M23 47
Ground Yes
52
B: M24 20
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Revision: March 2010 2008 QX56
WCS-18
< COMPONENT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
BCM (BODY CONTROL MODULE)
BCM (BODY CONTROL MODULE) : Diagnosis ProcedureINFOID:0000000004873061
1. CHECK FUSES AND FUSIBLE LINK
Check that the following fuses and fusible link are not blown.
Is the fuse blown?
YES >> Replace the blown fuse or fusible link after repairing the affected circuit.
NO >> GO TO 2
2. CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect BCM.
3. Check voltage between BCM harness connector and ground.
Is the measurement value normal?
YES >> GO TO 3
NO >> Repair or replace harness.
3. CHECK GROUND CIRCUIT
Check continuity between BCM harness connector and ground.
Does continuity exist?
YES >> INSPECTION END
NO >> Repair or replace harness.
Terminal No. Signal nameFuses and fusible link No.
57 Battery power supply 22 (15A)
70 F (50A)
11 Ignition ACC or ON 4 (10A)
38 Ignition ON or START 59 (10A)
ConnectorTe r m i n a l s
Power
source Condition
Voltage (V) (Ap-
prox.)
(+) (-)
M18 11 Ground
ACC
power
supply Ignition
switch
ACC or ON Battery voltage
38 Ground Ignition
power
supply Ignition
switch ON or START Battery voltage
M20 57 Ground
Battery
power
supply Ignition
switch
OFF Battery voltage
70 Ground Battery
power
supply Ignition
switch OFF Battery voltage
LIIA2415E
BCM
GroundContinuity
Connector Terminal
M20 67 Yes
LIIA0915E
Revision: March 2010 2008 QX56
WCS-22
< COMPONENT DIAGNOSIS >
KEY SWITCH SIGNAL CIRCUIT
KEY SWITCH SIGNAL CIRCUIT
DescriptionINFOID:0000000001697685
Transmits a key switch signal to the BCM.
Component Function CheckINFOID:0000000001697686
1.CHECK BCM INPUT SIGNAL
Select “DATA MONITOR” for “BCM” and check the “KEY ON SW” monitor value.
>> Inspection End.
Diagnosis ProcedureINFOID:0000000001697687
1.CHECK FUSE
Check if the key switch and ignition knob switch 10A fuse (No. 62, located in the fuse and relay box) is blown.
Is the fuse blown?
YES >> Be sure to repair the cause of malfunction before installing new fuse.
NO >> GO TO 2
2.CHECK BCM INPUT SIGNAL
Check voltage between BCM harness connector and ground.
Is the inspection result normal?
YES >> Inspection End.
NO >> GO TO 3
3.CHECK KEY SWITCH CIRCUIT
1. Disconnect BCM and key switch and ignition knob switch con- nectors.
2. Check continuity between BCM harness connector M18 (A) and key switch and ignition knob switch harness connector M12 (B).
3. Check continuity between BCM harness connector M18 (A) and ground.KEY ON SW
When key is inserted into key cylinder : ON
When key is removed from key cylinder : OFF
Te r m i n a l s
ConditionVo l ta g e
(Approx.)
(+)
(−)
BCM
connector Te r m i n a l
M18 37 Ground Key is inserted Battery voltage
Key is removed
0
PKIC0721E
AB
Continuity
Connector Terminal Connector Terminal
M183 7M 12 4 Y es
A GroundContinuity
Connector Terminal
M18 37 No
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Revision: March 2010 2008 QX56
WCS
KEY SWITCH SIGNAL CIRCUITWCS-23
< COMPONENT DIAGNOSIS >
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Is the inspection result normal?
YES >> GO TO 4
NO >> Repair harness or connector.
4.CHECK KEY SWITCH POWER SUPPLY CIRCUIT
Check voltage between key switch and ignition knob switch harness
connector and ground.
Is the inspection result normal?
YES >> Replace key switch and ignition knob switch.
NO >> Repair harness or connector.
Component InspectionINFOID:0000000001697688
1.CHECK KEY SWITCH
1. Turn ignition switch OFF.
2. Disconnect key switch and i gnition knob switch connector.
3. Check continuity between key switch and ignition knob switch terminals 3 and 4.
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace key switch and ignition knob switch.
Te r m i n a l s Vo l ta g e
(Approx.)
(+)
(−)
Key switch and ignition
knob switch connector Te r m i n a l
M12 3Ground Battery voltage
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3 – 4
When key is inserted
into key cylinder : Continuity should exist.
When key is removed
from key cylinder : Continuity should not exist.
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Revision: March 2010
2008 QX56