warning INFINITI QX56 2011 Factory Service Manual

COMPONENT PARTSDLN-11
< SYSTEM DESCRIPTION > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
Component DescriptionINFOID:0000000006222215
Transfer Control UnitINFOID:0000000006222216
 Transfer control unit operates transfer control act uator, 4WD warning lamp and 4WD mode indicator lamp
according to input signal from 4WD shift switch and each sensor and control unit.
 When 4WD system is malfunctioning, 4WD warning la mp turns ON and fail-safe status activates.
 When protection is necessary, 4WD warning la mp blinks and protection status activates.
Transfer Control ActuatorINFOID:0000000006222217
Transfer control actuator integrates transfer motor, transfer internal position sensor, and transfer motor tem-
perature sensor, and switches 4WD mode (AUTO ⇔4H ⇔4L).
TRANSFER MOTOR
Transfer motor operates according to signal from transfer control unit and switches 4WD mode
(AUTO ⇔4H ⇔4L). It also performs front and rear distri bution of traction force during AUTO mode.
TRANSFER INTERNAL SPEED SENSOR
Transfer internal speed sensor detects rotation status of transfer motor and transmits signal to transfer control
unit.
TRANSFER MOTOR TEMPERATURE SENSOR
 Transfer motor temperature sensor m easures temperature of transfer motor.
Component parts Reference/Function
Transfer control unit DLN-11, "
Transfer Control Unit"
Transfer control actua-
torTransfer motor
DLN-11, "
Transfer Control Actuator"
Transfer internal speed
sensorDLN-11, "Transfer Control Actuator"
Transfer motor temper-
ature sensor
DLN-11, "Transfer Control Actuator"
Transfer Hi-Lo position sensor
DLN-12, "Transfer Hi-Lo Position Sensor"
Transfer rotary position sensorDLN-12, "Transfer Rotary Position Sensor"
Transfer lock position sensorDLN-12, "Transfer Lock Position Sensor"
Transfer fluid temperature sensorDLN-12, "Transfer Fluid Temperature Sensor"
4WD mode switchDLN-18, "4WD SYSTEM : System Description"
4WD indicator lampDLN-18, "4WD SYSTEM : System Description"
4WD warning lampDLN-18, "4WD SYSTEM : System Description"
AT P w a r n i n g l a m pDLN-18, "4WD SYSTEM : System Description"
ABS actuator and electric unit (control unit)Transmits the following signals via CAN communication line to transfer control unit.
 Vehicle speed signal (ABS)
 Stop lamp switch signal (brake signal)
 ABS operation signal
 VDC operation signal
 TCS operation signal
Steering angle sensor Transmits the following signals via CAN communication line to transfer control unit.
 Steering angle sensor signal
ECM Transmits the following signals via CAN communication line to transfer control unit.
 Accelerator pedal position signal
 Engine speed signal
 Engine torque signal
TCM Transmits the following signals via CAN communication line to transfer control unit.
 Shift position signal
 Gear position signal
 Output shaft revolution signal
Revision: 2010 May2011 QX56

DLN-18
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
SYSTEM
SYSTEM
4WD SYSTEM
4WD SYSTEM : System DescriptionINFOID:0000000006222224
 In AUTO mode, distribution of traction force is cont
rolled from 2WD status (0:100) to 4WD status (50:50)
according to signal from each sensor and switch.
 In accordance with fail-safe function, when system is malfunctioning, 4WD warning lamp on combination meter turns ON and 4WD control stops. For fail-safe function, refer to DLN-20, "
4WD SYSTEM : Fail-Safe".
 When a high load status continues for transfer assembly (transfer control actuator or transfer fluid), 4WD
control temporarily becomes 4H or 2WD status, according to protection function.
NOTE:
4WD system is not malfunctioning.
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL
It transmits/receives each signal from the followi ng transfer control unit via CAN communication line.
JPDIE0272GB
Component parts Control signal
ABS actuator and electric unit (control unit) Transmits the following signals via CAN communication line to transfer control unit.
 Vehicle spee
d signal (ABS)
 Stop lamp switch signal (brake signal)
 ABS operation signal
 VDC operation signal
 TCS operation signal
ECM Transmits the following signals via CAN communication line to transfer control unit.
 Accelerator pedal position signal
 Engine speed signal
 Engine torque signal
Revision: 2010 May2011 QX56

SYSTEMDLN-19
< SYSTEM DESCRIPTION > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
4WD SHIFT SWITCH AND 4WD SHIFT INDICATOR LAMP
*1: Blinking 2 times/1 second
*2: “4HI” and “4LO” blink alternately.
CONDITION FOR TURN ON THE WARNING LAMP
TCM Transmits the following signals via CAN communication line to transfer control unit.
 Shift position signal
 Gear position signal
 Output shaft revolution signal
Steering angle sensor Transmits the following signals via CAN communication line to transfer control unit.
 Steering angle sensor signal
Combination meter Receives the following signals via CAN communication line from transfer control unit.
 4WD warning lamp signal
 ATP warning lamp signal
 4WD mode indicator signal
Component parts Control signal
4WD shift switch 4WD shift indicator lamp (in Information display) 4WD shift procedure
AUTO
1. Start the engine.
2. Turn the 4WD shift switch.
NOTE:
Mode can be switched between AU-
TO⇔4H while driving straight.
4H
↓↑
4WD status: 4H ⇔4L (Blinking)
*1*2
1. Start the engine.
2. Never drive the vehicle.
3. Shift A/T shift selector to N position.
4. Press and rotate 4WD shift switch
while depressing brake pedal.
CAUTION:
4WD mode does not switch when 4WD
shift switch is operated while the vehi-
cle is running or A/T shift selector is
shifted to any position other than neu-
tral.
4L
JPDIE0230ZZJPDIE0234ZZ
JPDIE0231ZZJPDIE0235ZZ
JPDIE0231ZZ
JPDIE0233ZZ
JPDIE0236ZZ
JPDIE0233ZZJPDIE0237ZZ
Revision: 2010 May2011 QX56

DLN-20
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
SYSTEM
4WD Warning Lamp
 Turns ON when there is a malfunction in 4WD system. 4W
D warning lamp indicates the vehicle is in fail-safe
mode.
 Also turns ON when ignition switch is turned ON, fo r the purpose of lamp check. Turns OFF approximately
for 1 second after the engine starts if system is normal.
ATP Warning Lamp
When the A/T shift selector is in P position, the vehicle may move if the transfer case in neutral. ATP warning
lamp is turned on to indicate this condition to the driver.
CONDITION FOR OPERATE WARNING BUZZER
For preventing an incorrect operation during 4H ⇔4L switching, warning buzzer sounds from inside of transfer
control unit and warns the driver, when certain conditions are satisfied.
4WD SYSTEM : Fail-SafeINFOID:0000000006303692
 If any malfunction occurs in 4WD electrical system, and control unit detects the malfunction, 4WD warning
lamp on combination meter turns ON to indicate system malfunction.
 When 4WD warning lamp is ON, vehicle changes to rear-wheel drive or shifts to 4-wheel drive (front-wheels
still have some driving torque).
Condition 4WD warning lamp
Lamp check Turns ON when ignition switch is turned ON. Turns OFF ap-
prox. 1 second after the engine start.
4WD system malfunction ON
Protection function is activated due to heavy load to transfer assem-
bly. (4WD system is not malfunctioning.) Quick blinking: 2 times/second
(Blinking in approx. 1 minute and then turning OFF)
Large difference in diameter of front/rear tires Slow blinking: 1 time/2 seconds
(Continuing to blink until turning ignition switch OFF)
Other than above (system normal) OFF
Condition Warning buzzer
4WD shift status A/T shift selector Engine speed
4H⇔4L N range 350
− 1.600 rpm OFF
Under 350 rpm or over 1.600 rpm ON
Except N range Always
Revision: 2010 May2011 QX56

DLN-22
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
DIAGNOSIS SYSTEM (T
RANSFER CONTROL UNIT)
ABS OPER [On/Off] X ABS operation status via CAN communication
line is displayed.
SAND MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
ROCK MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
SNOW MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
ONROAD MODE IND [On/Off] This indicator is not equipped, but it is dis-
played.
SAND MODE SW [On/Off] X This switch is not equipped, but it is displayed.
ROCK MODE SW [On/Off] X This switch is not equipped, but it is displayed.
SNOW MODE SW [On/Off] X This switch is not equipped, but it is displayed.
ONROAD MODE SW [On/Off] X This switch is not equipped, but it is displayed.
HI/LO POSI SEN 3 [On/Off] X Transfer Hi-Lo position sensor (3) status is dis-
played.
HI/LO POSI SEN 1 [On/Off] X Transfer Hi-Lo position sensor (1) status is dis-
played.
LOCK POSI SEN [OPEN/LOCK/BAT/UNLEAN/HI
TEMP/ERROR/GND] X
Transfer lock position sensor signal is dis-
played.
ATP IND [On/Off] Control status of ATP warning lamp is dis-
played.
4WD FAILLAMP [On/Off] X Control status of ATP warning lamp is dis-
played.
4WD MODE IND [4L/LOCK/AUTO] X Control status of 4WD mode indicator lamp is
displayed.
(LOCK means 4H of 4WD mode)
MOTOR DRIVE B [HI/LO/PWM] X Driving status of transfer motor is displayed.
(Reverse side)
MOTOR DRIVE A [HI/LO/PWM] X Driving status of transfer motor is displayed.
(Drive side)
FLUID TEMP SEN [V] X Temperature of transfer fluid is displayed.
MOTOR TEMP [V] X Temperature of transfer motor is displayed.
C/U POWER SUP [V] X Power supply voltage value of transfer control
unit is displayed.
MOTOR POWER SUP [V] X Power supply voltage value of transfer motor
unit is displayed.
ROTARY POSI SEN [%] X Transfer rotary position sensor signal is dis-
played.
THRTL POSI SEN [%] X X Throttle opening status via CAN communica-
tion line is displayed.
AT R SPEED [km/h] X Output shaft revolution speed via CAN commu-
nication line is displayed.
T/M GEAR [0 - 7] X Current transmission gear via CAN communi-
cation line is displayed.
COMPR VHCL SPEED [km/h] X Vehicle speed calculated by transfer control
unit is displayed.
VHCL/S SEN-FR [km/h] X Wheel speed (front) average calculated by
transfer control.
Monitor item (Unit)
SELECT MONITOR ITEM
Remarks
ECU INPUT
SIGNALS MAIN SIG-
NALS
Revision: 2010 May2011 QX56

TRANSFER CONTROL UNITDLN-25
< ECU DIAGNOSIS INFORMATION > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
HI-LO POSI SEN 3 4WD mode: AUTO or 4H ON
4WD mode: Shifting OFF
4WD mode: 4L OFF
HI-LO POSI SEN 1 4WD mode: AUTO or 4H ON
4WD mode: Shifting ON
4WD mode: 4L OFF
LOCK POSI SEN When lock sleeve is opening OPEN
When lock sleeve locking LOCK
When transfer lock position sensor
signal circuit is short. (Battery
short) BAT
When transfer lock position sensor is unlearned. UNLEAN
When the temperature of transfer lock position sensor is high. HI TMP
When transfer lock position sensor is malfunctioning. ERROR
When transfer lock position sensor signal circuit is short. (Ground
short) GND
AT P I N D ATP lamp: ON ON
AT P l a m p : O F F O F F
4WD FAIL LAMP 4WD warning lamp: ON ON
4WD warning lamp: OFF OFF
4WD MODE IND 4WD shift switch: AUTO AUTO
4WD shift switch: 4H LOCK
4WD shift switch: 4L 4L
MOTOR DRIVE B When transfer motor is driving in reversal. (100% duty controlled) HI
When transfer motor is driving or stopping. LO
When transfer motor is driving in reversal. (PWM output) PWM
MOTOR DRIVE A When transfer motor is driving. (100% duty controlled) HI
When transfer motor is driving in reversal or stopping. LO
When transfer motor is driving. (PWM output) PWM
FLUID TEMP SE The temperature of transfer fluid is 20 – 80 °C. Approx. 1.1 – 0.3 V
MOTOR TEMP The temperature of transfer motor is 20 – 80 °C. Approx. 1.1 – 0.3 V
C/U POWER SUP Always Battery voltage
MOTOR POWER SUP Always Battery voltage
ROTARY POSI SEN 4WD mode: AUTO
A/T shift selector: DDepress the accelerator pedal several
times.
Value is changing
THRTL POS SEN When depressing accelerator pedal
(Value rises gradually in response to throttle position) 0 – 100 %
AT R SPEED Vehicle stopped 0.00 km/h (0.00 mph)
Vehicle driving (4WD mode: AUTO)
CAUTION:
Check air pressure of tire under standard condition. Approx. equal to the indication
on speedometer (inside of ±10
%)
T/M GEAR A/T shift selector: D
Vehicle driving 1
2
3
4
5
6
7
Monitor item Condition Value/Status
Revision: 2010 May2011 QX56

DLN-28
< ECU DIAGNOSIS INFORMATION >[TRANSFER: ATX90A]
TRANSFER CONTROL UNIT
CAUTION:
When using circuit tester to measure voltage for in
spection, be sure not to extend forcibly any con-
nector terminals.
Fail-SafeINFOID:0000000006222228
 If any malfunction occurs in 4WD electrical system, and control unit detects the malfunction, 4WD warning
lamp on combination meter turns ON to indicate system malfunction.
 When 4WD warning lamp is ON, vehicle changes to rear-wheel drive or shifts to 4-wheel drive (front-wheels
still have some driving torque).
29
(LG/R) Ground Hi-Lo position sensor 2
Input/
Output Engine
running
(Never
drive the
vehicle.)
Always 0 V
30
(R/B) Ground Transfer lock position
sensor (GND) —Always 0 V
31
(L/O) Ground Transfer internal speed
sensor (DIR)
Input IGN ONWhen changing the trans-
fer motor rota
tion direc-
tion.
32
(BR/R) Ground IGN SW Input IGN ON Battery voltage
IGN OFF 0V
35
(R) Ground 4WD shift SW (4H) Input IGN ON 4WD shift switch: 4H Battery voltage
4WD shift switch: Except
4H
0 V
36
(L/R) Ground Transfer fluid tempera-
ture sensor (GND)
—Always 0 V
38
(G/O) Ground
Transfer lock position
sensor signal Input IGN ON
39
(R/W) Ground Transfer internal speed
sensor power supply
InputIGN ON 8 V
IGN OFF 0V
41
(W/R) Ground Transfer control actuator
power supply Input Always Battery voltage
43
(G/R) Ground Motor drive B Input/
Output Transfer motor driving 0V - Battery voltage
44
(B) Ground GND — Always 0 V
45
(G/Y) Ground Motor drive A Input/
Output Transfer motor driving 0V - Battery voltage
46
(B) Ground Transfer control actuator
(GND)
—Always 0 V
Te r m i n a l N o .
(Wire color) Description
Condition Value (Approx.)
+ - Signal name Input/
Output
JPDIE0269GB
JPDIE0268GB
Revision: 2010 May2011 QX56

DIAGNOSIS AND REPAIR WORK FLOWDLN-39
< BASIC INSPECTION > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
YES >> GO TO 7.
NO >> Check harness and connectors based on the in formation obtained by interview. Refer to GI-40,
"Intermittent Incident".
7.FINAL CHECK
With CONSULT-III
1. Check the reference value for “ALL MODE AWD/4WD”.
2. Recheck the symptom and check that symptom is not reproduced on the same conditions.
Is the symptom reproduced?
YES >> GO TO 3.
NO >> INSPECTION END
Diagnostic Work SheetINFOID:0000000006222233
Description
 In general, customers have their own criteria for a pr oblem. Therefore, it is important to understand the
symptom and status well enough by asking the customer about his/her concerns carefully. To systemize all
the information for the diagnosis, prepare the in terview sheet referring to the interview points.
 In some cases, multiple conditions that appear simultaneously may cause a DTC to be detected.
Interview sheet sample
Interview sheet
Customer
name MR/MSRegistration
number
Initial year reg-
istration
Vehicle type VIN
Storage
date Engine Mileage km ( Mile)
Symptom †
Vehicle does not enter 4WD mode.
† 4WD warning la mp turns on.
† Heavy tight-corner braking symptom occurs
† Noise †Vibration
† Others
( )
First occurrence †Recently †Others ( )
Frequency of occurrence †Always †Under a certain conditions of †Sometimes (time(s)/day)
Climate
conditions †
Irrelevant
Weather †Fine †Cloud †Rain †Snow †Others ( )
Temperature †Hot †Warm †Cool †Cold †Temperature [Approx. °C ( °F)]
Relative humidity †High †Moderate †Low
Road conditions †
Urban area †Suburb area †High way
† Mounting road (uphill or down hill) †Rough road
Operation conditions, etc. †
Irrelevant
† When engine starts †During idling
† During driving †During acceleration †At constant speed driving
†During deceleration †During cornering (right curve or left curve)
Revision: 2010 May2011 QX56

P1808 WHEEL SPEED SENSORDLN-53
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P1808 WHEEL SPEED SENSOR
DTC LogicINFOID:0000000006222248
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Start the engine and drive at 30 km/h (19 MPH) or more for approximately 1minute.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1808” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-53, "DTC Logic".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222249
1.PERFORM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ABS”.
Is any DTCs detected?
YES >> Check the DTCs.
NO >> GO TO 2.
2.ERASE SELF-DIAGNOSTIC RESULT
With CONSULT-III
1. Erase self-diagnostic results for “ALL MODE AWD/4WD”.
2. Start the engine and drive vehicle at 30 km/h (19 MPH) or more.
3. Check that ABS warning lamp turns OFF.
Does ABS warning lamp turn OFF?
YES >> GO TO 3.
NO >> Refer to BRC-122, "
Diagnosis Procedure".
3.CHECK TERMINALS AND HARNESS CONNECTORS
Check transfer control unit pin terminals for damage or loose connection with harness connector.
Is inspection result normal?
YES >> After turning the ignition switch OFF, perform DTC confirmation procedure again. When DTC
"P1808" is detected, Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
NO >> Repair or replace error-detected parts.
DTC Display item Malfunction detected condition Possible cause
P1808 VHCL SPEED SEN-ABS  Malfunction is detected in vehicle
speed signal that is output from ABS
actuator and electric unit (control unit)
through CAN communication.
 Improper signal is input while driving.  Harness or connector (CAN communi-
cation line)
 Malfunction of ABS actuator and elec-
tric unit (control unit)
- Malfunction of ABS actuator and elec-
tric unit (control unit) circuit error
- Vehicle speed signal error
Revision: 2010 May2011 QX56

DLN-88
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1830 ABS OPERATION SIGNAL
P1830 ABS OPERATION SIGNAL
DTC LogicINFOID:0000000006222294
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Start the engine and drive at 30 km/h (19 MPH) or more.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1830” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-88, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222295
1.PERFORM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ABS”.
Is any DTCs detected?
YES >> Check the DTCs.
NO >> GO TO 2.
2.ERASE SELF-DIAGNOSTIC RESULT
With CONSULT-III
1. Erase self-diagnostic results for “ALL MODE AWD/4WD”.
2. Start the engine and drive vehicle at 30 km/h (19 MPH) or more.
3. Check that ABS warning lamp turns OFF.
Does ABS warning lamp turn OFF?
YES >> GO TO 3.
NO >> Refer to BRC-123, "
Diagnosis Procedure".
3.CHECK TERMINALS AND HARNESS CONNECTORS
Check transfer control unit pin terminals for damage or loose connection with harness connector.
Is inspection result normal?
YES >> After turning the ignition switch OFF, perform DTC confirmation procedure again. When DTC
"P1830" is detected, Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
NO >> Repair or replace error-detected parts.
DTC Display item Malfunction detected condition Possible cause
P1830 ABS OP SIG Malfunction is detect
ed in ABS operation
signal that is outp ut from ABS actuator
and electric unit (control unit) through
CAN communication. Malfunction of ABS system
Revision: 2010 May2011 QX56