2008 INFINITI QX56 display

DIAGNOSIS SYSTEM (TRANSFER CONTROL UNIT)DLN-19
< FUNCTION DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
12. Move A/T selector lever to N position.
13. Turn 4WD shift switch to AUTO position.
14. Move A/T selector lever to P position.
15. Read the flickering of 4WD warning lamp.
Self-diagnosis example
ERASE SELF-DIAGNOSIS
• In order to make it easier to find the cause of hard-to-duplicate malfunctions, malfunction information is
stored into the control unit as necessary during use by the user. This memory is not erased no matter how
many times the ignition switch is turned ON and OFF.
• However, this information is erased by turning igni tion switch OFF after performing self-diagnostics or by
erasing the memory using the CONSULT-III.
DATA MONITOR MODE
Operation Procedure
1. Connect CONSULT-III.
2. Touch DATA MONITOR.
3. Select from SELECT MONITOR ITEM, screen of data monitor mode is displayed.
NOTE:
When malfunction is detected, CONSUL T-III performs REAL-TIME DIAGNOSIS.
Also, any malfunction detected while in th is mode will be displayed at real time.
Display Item List
×: Standard –: Not applicable
PDIA0227E
Monitored item (Unit) Monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM MENU
VHCL/S SEN·FR [km/h] or [mph] ×–×Wheel speed calculated by ABS actuator and
electric unit (control unit).
Signal input with CAN communication line.
VHCL/S SEN·RR [km/h] or [mph] ×–×Wheel speed calculated by TCM.
Signal input with CAN communication line.
ENGINE SPEED [rpm] ×–×Engine speed calculated by ECM.
Signal input with CAN communication line.
THRTL POS SEN [V] ×–×Accelerator peda
l position (APP) sensor sig-
nal voltage is displayed.
Signal input with CAN communication line.
FLUID TEMP SE [V] ×–×Transfer fluid temperature sensor signal volt-
age is displayed.
BATTERY VOLT [V] ×–×Power supply voltage for transfer control unit.
2WD SWITCH [ON/OFF] ×–×4WD shift switch status is displayed.
AUTO SWITCH [ON/OFF] ×–×4WD shift switch status is displayed.
LOCK SWITCH [ON/OFF] ×–×4WD shift switch status is displayed.
(LOCK means 4H of 4WD shift switch.)
Revision: March 2010
2008 QX56

DLN-20
< FUNCTION DIAGNOSIS >[ATX14B]
DIAGNOSIS SYSTEM (T
RANSFER CONTROL UNIT)
4L SW [ON/OFF] ×–×4WD shift switch status is displayed.
(4L means 4LO of 4WD shift switch.)
N POSI SW TF [ON/OFF] ×–×Neutral-4LO switch signal status is displayed.
ATP SWITCH [ON/OFF] ×–×ATP switch signal status is displayed.
WAIT DETCT SW [ON/OFF] ×–×Wait detection switch status is displayed.
LINE PRES SW [ON/OFF] ×–×Line pressure switch status is displayed.
CL PRES SW [ON / OFF] ×–×Clutch pressure switch status is displayed.
N POSI SW AT [ON/OFF] ×–×N position signal of A/T transmission range
switch status is displayed.
Signal input with CAN communication line.
R POSI SW AT [ON/OFF] ×–×R position signal of A/T transmission range
switch status is displayed.
Signal input with CAN communication line.
P POSI SW AT [ON/OFF] ×–×P position signal of A/T transmission range
switch status is displayed.
Signal input with CAN communication line.
ABS OPER SW [ON/OFF] ×–×ABS operation signal status is displayed.
Signal input with CAN communication line.
VDC OPER SW [ON/OFF] ×–×VDC operation signal status is displayed.
Signal input with CAN communication line.
TCS OPER SW [ON/OFF] ×–×TCS operation signal status is displayed.
Signal input with CAN communication line.
THROTTLE POSI [0.0/8] –×× Thottle position status is displayed.
Signal input with CAN communication line.
4WD MODE [AUTO/LOCK/2WD/4L] – ××Control status of 4WD recognized by transfer
control unit. (AUTO, 4H, 2WD or 4LO)
VHCL/S COMP [km/h] or [mph] –×× Vehicle speed recognized by transfer control
unit.
COMP CL TORQ [kgm] –×× Calculated torque recognized by transfer con-
trol unit.
DUTY SOLENOID [%] –×× Control value of clutch pressure solenoid.
2-4WD SOL [ON/OFF] –×× Output condition to 2-4WD solenoid.
2-4WD SOL MON [ON/OFF] ––×Check signal for transfer control unit signal
output.
MOTOR RELAY [ON/OFF] –×× Transfer motor relay signal status is dis-
played.
MOTOR RELAY MON [ON/OFF] ––×Check signal for transfer control unit signal
ou
tpu
t

.
4WD FAIL LAMP [ON/OFF] –×× Control status of 4WD warning lamp is dis-
played.
2WD IND [ON/OFF] ––×Control status of 4WD shift indicator lamp
(2WD indicator lamp) is displayed.
AUTO IND [ON/OFF] ––×Control status of 4WD shift indicator lamp
(2WD and AUTO indicator lamp) is displayed.
LOCK IND [ON/OFF] ––×Control status of 4WD shift indicator lamp
(2WD, AUTO and Lock indicator) is displayed.
4L IND [ON/OFF] –– ×Control status of 4LO indicator lamp is dis-
played.
Monitored item (Unit)
Monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM
MENU
Revision: March 2010 2008 QX56

DIAGNOSIS SYSTEM (TRANSFER CONTROL UNIT)DLN-21
< FUNCTION DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
WORK SUPPORT
When there is no malfunction with transfer and 4WD sys tem, the following symptoms in AUTO mode may be
claimed by a customer: vibration when accelerating on a low µ road (snow-covered or icy road) or a slight
shock is felt at a few hertz as if it were being pushed lightly from behind.
It is possible to deal with these symptoms by changing the CLUTCH FORCE RELEASE LIMIT VALUE. How-
ever, be careful when changing the value because it may adversely affect driving performance.
Operation Procedure
1. Connect CONSULT-III.
2. Touch WORK SUPPORT.
3. Select from CLUTCH/F RLS LIM ADJ, screen of data monitor mode is displayed.
Clutch Force Release Limit Adjustment
1. Initial CLUTCH FORCE RELEASE LIMIT value 0.3 kgm appears under CONDITION SETTING on CON-
SULT-III display.
2. Touch 1.2 on the display.
3. Display changes to NOW ADJUSTING in a short time.
4. When clutch force release limit value is set to 1.2 kgm, current value 0.3 kgm shown on display will be replaced by 1.2 kgm and ADJUSTME NT COMPLETE will appear at the same time. Clutch force release
limit value setting is now complete.
ATP IND [ON/OFF] ––×Control status of ATP warning lamp is dis-
played.
SHIFT POS SW1 [ON/OFF] ×–×Actuator position switch 1 (Low) signal status
is displayed.
SHIFT POS SW2 [ON/OFF] ×–×Actuator position switch 2 (high) signal status
is displayed.
SHIFT ACT1 [ON/OFF] –×× Output condition to actuator motor (clockwise)
SHIFT AC MON1 [ON/OFF] ×–×Check signal for transfer control unit signal
output
SHIFT ACT2 [ON/OFF] –×× Output condition to actuator motor (counter-
clockwise)
SHIFT AC MON2 [ON/OFF] ×–×Check signal for transfer control unit signal
output
T/F F SPEED [km/h] or [mph] ×–×Displayed, but do not use.
A/T R SPEED [km/h] or [mph] ×–×Output speed sensor signal calculated by
TCM.
Signal input with CAN communication line.
AT GEAR POSI [1/2/3/4/5] ×–×A/T actual gear position is displayed.
Monitored item (Unit)
Monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM
MENU
1.2 kg-m : Tight corner braking symptom is alleviated. However, vibration may occur when acceler-
ating on a low µ road (icy road, etc.).
0.3 kg-m : Initial set value.
0.2 kg-m : Do not set to th is value because the tight
corner braking symptom will get worse.
Revision: March 2010 2008 QX56

DLN-24
< COMPONENT DIAGNOSIS >[ATX14B]
P1802 – P1804, P1809 TRANSFER CONTROL UNIT
P1802 – P1804, P1809 TRANSFER CONTROL UNIT
DescriptionINFOID:0000000001737105
The transfer control unit controls the transfer contro
l device which controls shifts between AUTO, 4H and 4LO
and between 2WD and 4WD. A DTC may set when any of the following occur:
• Malfunction is detected in the memory (RAM) system of transfer control unit.
• Malfunction is detected in the memory (ROM) system of transfer control unit.
• Malfunction is detected in the memory (E EPROM) system of transfer control unit.
• AD converter system of transfer control unit is malfunctioning.
DTC LogicINFOID:0000000001737106
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Are DTC's P1802 - P1804 or P1809 detected?
YES >> Perform diagnosis procedure. Refer to DLN-24, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000001737107
1.INSPECTION START
Do you have CONSULT-III?
YES or NO
YES >> GO TO 2.
NO >> GO TO 3.
2.PERFORM SELF-DIAGNOSIS (WITH CONSULT-III)
With CONSULT-III
1. Turn ignition switch ON. (Do not start engine.)
2. Select SELF-DIAG RESULTS mode for ALL MODE AWD/4WD with CONSULT-III.
3. Touch ERASE.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Perform the self-diagnosis again.
Is the CONTROL UNIT 1 [P1802], CONTROL UNIT 2 [P1803], CONTRO L UNIT 3 [P1804] or CONTROL
UNIT 4 [P1809] displayed?
YES >> Replace transfer control unit. Refer to DLN-128, "Removal and Installation".
NO >> Inspection End.
3.PERFORM SELF-DIAGNOSIS (WITHOUT CONSULT-III)
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1802] CONTROL UNIT 1 Malfunction is detected in the memory
(RAM) system of transfer control unit.
Refer to DLN-24
.
[P1803] CONTROL UNIT 2
Malfunction is detected in the memory
(ROM) system of transfer control unit.
[P1804] CONTROL UNIT 3 Malfunction is detected in the memory
(EEPROM) system of transfer control
unit.
[P1809] CONTROL UNIT 4 AD converter system of transfer control
unit is malfunctioning.
Revision: March 2010
2008 QX56

P1808 VEHICLE SPEED SENSOR (ABS)DLN-27
< COMPONENT DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P1808 VEHICLE SPEED SENSOR (ABS)
DescriptionINFOID:0000000001737111
The ABS actuator and electric unit (control unit) transmits a vehicle speed signal via CAN communication to
the transfer control unit. DTC P1808 sets when a malfunction is detected in the vehicle speed signal that is
output from the ABS actuator and electric unit (control unit) or an improper signal is input while driving.
DTC LogicINFOID:0000000001737112
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1808 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-27, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000001737113
1.CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to BRC-24, "
CONSULT-III
Function (ABS)".
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.
2.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-80, "
Reference Value".
Are the inspection results normal?
YES >> GO TO 3.
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
3.CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
Are the inspection results normal?
YES >> Inspection End.
NO >> Perform self-diagnosis with ABS actuator and electric unit (control unit) again.
DTC CONSULT-III Diagnostic item is detected when... Reference
[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. Refer to DLN-27
.
Revision: March 2010
2008 QX56

DLN-28
< COMPONENT DIAGNOSIS >[ATX14B]
P1810 NEUTRAL-4LO SWITCH
P1810 NEUTRAL-4LO SWITCH
DescriptionINFOID:0000000001737114
The neutral-4LO switch detects that the transfer case
is in neutral or 4LO range. DTC P1810 will set when an
improper signal from the neutral-4LO switch is input due to an open or short circuit.
DTC LogicINFOID:0000000001737115
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1810 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-28, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000001737116
1.CHECK 4LO POSITION SWITCH SIGNAL
With CONSULT-III1. Start engine.
2. Select DATA MONITOR mode for ALL MODE AWD/4WD with CONSULT-III.
3. Read out the value of N POSI SW TF.
Without CONSULT-III
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1810] 4L POSI SW TF Improper signal from neutral-4LO switch
is input due to open or short circuit.Refer to
DLN-28
.
Condition Display value
• Vehicle stopped
• Engine running
• A/T selector lever N position
• Brake pedal depressed 4WD shift switch: 2WD,
AUTO or 4H
OFF
4WD shift switch: 4H to
4LO (While actuator mo-
tor is operating.) OFF
→ ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.) ON
→ OFF
4WD shift switch: 4LO ON
SDIA2693E
Revision: March 2010 2008 QX56

P1813 4WD SHIFT SWITCHDLN-31
< COMPONENT DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P1813 4WD SHIFT SWITCH
DescriptionINFOID:0000000001737118
The 4WD shift switch allows the driver to select AUTO, 2WD or 4WD and 4H or 4LO. DTC P1813 will set if
more than two switch inputs are simultaneously detected by the transfer control unit due to a short circuit in the
4WD shift switch.
DTC LogicINFOID:0000000001737119
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1813 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-31, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000001737120
1.CHECK 4WD SHIFT SWITCH SIGNAL
With CONSULT-III
1. Turn ignition switch ON. (Do not start engine.)
2. Select DATA MONITOR mode for ALL MODE AWD/4WD with CONSULT-III.
3. Read out ON/OFF switching action of the 2WD SWITCH, AUTO SWITCH, LOCK SWITCH, 4L SW with
operating 4WD shift switch.
Without CONSULT-III
1. Turn ignition switch ON. (Do not start engine.)
2. Check voltage between transfer control unit harness connector
terminals and ground.
Are inspection results normal?
YES >> GO TO 5.
NO >> GO TO 2.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1813] 4WD MODE SW More than two switch inputs are simulta-
neously detected due to short circuit of
4WD shift switch.Refer to DLN-31
.
Connector Terminal
ConditionVoltage (Ap-
prox.)
E142 9 - ground
4WD shift switch: 2WD
Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
18 - ground 4WD shift switch: 4H
Battery voltage
4WD shift switch: 2WD, AUTO or
4LO 0V
23 - ground 4WD shift switch: 4LO
Battery voltage
4WD shift switch: 2WD, AUTO or 4H 0V
24 - ground 4WD shift switch: AUTO
Battery voltage
4WD shift switch: 2WD, 4H or 4LO 0V
WDIA0148E
Revision: March 2010 2008 QX56

P1814 WAIT DETECTION SWITCHDLN-35
< COMPONENT DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P1814 WAIT DETECTION SWITCH
DescriptionINFOID:0000000001737122
The wait detection switch detects if the transfer case is in 4WD. DTC P1814 will set if an improper signal from
the wait detection switch is input due to open or short circuit.
DTC LogicINFOID:0000000001737123
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1814 detected?
YES >> Perform diagnosis procedure. Refer to DLN-35, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000001737124
1.CHECK WAIT DETECTION SWITCH SIGNAL
With CONSULT-III
1. Start engine.
2. Select DATA MONITOR mode for ALL MODE AWD/4WD with CONSULT-III.
3. Read out the value of WAIT DETCT SW.
Without CONSULT-III
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1814] 4WD DETECT SWITCH Improper signal from wait detection
switch is input due to open or short cir-
cuit.
Refer to DLN-35
.
Condition
Display value
• Vehicle stopped
• Engine running
• A/T selector lever N position
• Brake pedal depressed 4WD shift switch: 2WD, AUTO
or 4H
OFF
4WD shift switch: 4H to 4LO
(While actuator motor is operat-
ing.) OFF
→ ON
4WD shift switch: 4LO to 4H
(While actuator motor is operat-
ing.) ON
→ OFF
4WD shift switch: 4LO ON
SDIA2701E
Revision: March 2010 2008 QX56