warning INFINITI QX56 2009 Factory Service Manual

DLN-8
< BASIC INSPECTION >[ATX14B]
DIAGNOSIS AND REPAIR WORKFLOW
Does 4WD warning lamp turn ON?
YES >> GO TO CHECK AT IDLE.
NO >> GO TO
DLN-105, "Diagnosis Procedure"
.
CHECK AT IDLE
1.CHECK 4WD SHIFT INDICATOR LAMP
1. Park vehicle on flat surface and engage the parking brake.
2. Turn ignition switch to OFF position.
3. Move A/T selector lever to P position.
4. Set 4WD shift switch to 2WD position.
5. Start engine.
Does 4WD shift indicator lamp turn ON?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK 4WD WARNING LAMP
Check 4WD warning lamp state.
Is 4WD warning lamp turned ON?
YES >> Perform the self-diagnosis. Refer to DLN-18, "CONSULT-III Function (ALL MODE AWD/4WD)".
NO >> Refer to DLN-107, "Diagnosis Procedure"
.
3.CHECK 4WD SHIFT INDICATOR AND 4LO INDICATOR OPERATION
1. Brake pedal depressed.
2. Move A/T selector lever to N position.
3. Set 4WD shift switch to 2WD, AUTO, 4H, 4LO, 4H, AUTO and 2WD in order. (Stay at each switch position for at least 1 sec-
ond.)
Do 4WD shift indicator and 4LO indicator lamps change properly?
Does buzzer sound?
YES >> GO TO CRUISE TEST.
NO >> GO TO DLN-107, "Diagnosis Procedure"
.
CRUISE TEST
1.CHECK INPUT SIGNAL
1. Warm up engine to normal operating temperature.
2. Park vehicle on flat surface.
3. Move A/T selector lever to P position.
4. Set 4WD shift switch to AUTO position.
5. Start engine.
6. Drive vehicle for at least 30 seconds at a speed higher than 20 km/h (12 MPH).
Is 4WD warning lamp turned ON?
On steady>>Perform the self-diagnosis. Refer to DLN-18, "CONSULT-III Function (ALL MODE AWD/4WD)".
WDIA0136E
Revision: December 20092009 QX56

DLN-10
< FUNCTION DIAGNOSIS >[ATX14B]
4WD SYSTEM
FUNCTION DIAGNOSIS
4WD SYSTEM
System DiagramINFOID:0000000003772075
COMPONENT DESCRIPTION
WDIA0164E
Components Function
Transfer control unit Controls transfer control device, control valves and shifts between 2WD/4WD and 4H/4LO.
Transfer control device Integrates actuator motor and actuator position switch.
2-4WD shift solenoid valve Controls oil pressure and allows shifting between 2WD and 4WD.
Clutch pressure solenoid valve Controls oil pressure and distributes torque between front and rear tires.
Line pressure switch Detects line pressure.
Clutch pressure switch Detects clutch pressure.
Transfer fluid temperature sensor Detects transfer fluid temperature.
Actuator motor Moves shift rods when signaled by transfer control unit.
Actuator position switch Detects actuator motor position.
Wait detection switch Detects whether or not 4WD lock gear is locked.
4LO switch Detects if transfer case is in 4LO.
ATP switch Detects if transfer case is in neutral.
4WD shift switch Allows driver to select from 2WD/4WD, 4H/4LO and AUTO.
4WD warning lamp • Illuminates if malfunction is detected in 4WD system.
 Flashes (1 flash / 2 seconds) if large difference in diameter of front and rear tires.
 Flashes (2 flashes / 1 second) if high transfer fluid temperature is detected.
AT P w a r n i n g l a m p Indicates that A/T parking mechanism does not operate when A/T selector lever is in P position
because transfer case is in neutral.
4WD shift indicator lamp Displays driving range selected by 4WD shift switch.
4LO indicator lamp Displays 4LO range.
Revision: December 20092009 QX56

4WD SYSTEMDLN-13
< FUNCTION DIAGNOSIS > [ATX14B]
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Hydraulic Control Circuits
TRANSFER CONTROL UNIT
 Transfer control unit controls transfer control dev
ice and it directs shifts from 4H-4LO and 2WD-4WD.
 Self-diagnosis can be done.
TRANSFER SHIFT HIGH AND LOW RELAYS
Transfer shift high and low relays apply power supply to transfer control device (actuator motor).
TRANSFER SHUT OFF RELAY
Transfer shut off relay applies power supply to transfer motor relay.
4WD SHIFT SWITCH AND INDICATOR LAMPS
4WD Shift Switch
Able to select from 2WD, AUTO, 4H or 4LO.
4WD Shift Indicator Lamp
 Displays driving conditions selected by 4WD shift switch with 2WD, AUTO and 4H indicators while engine is running. (When 4WD warning lamp is turned on, all 4WD shift indicator lamps are turned off.)
 Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4LO Indicator Lamp
LDIA0055E
WDIA0163E
Revision: December 20092009 QX56

DLN-14
< FUNCTION DIAGNOSIS >[ATX14B]
4WD SYSTEM
 Displays 4LO condition while engine is running. 4LO indi
cator lamp flashes if transfer gear does not shift
completely under 2WD, AUTO, 4H ⇔4LO. (When 4WD warning lamp is turned on, 4LO indicator lamp is
turned off.)
 Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4WD WARNING LAMP
Turns on or flashes when there is a malfunction in 4WD system.
Also turns on when ignition switch is turned ON, for purpose of lamp che\
ck. Turns OFF approximately 1 sec-
ond after the engine starts if system is normal.
4WD Warning Lamp Indication
ATP WARNING LAMP
When the A/T selector lever is in P position, the vehicle may move if the transfer case is in neutral. ATP warn-
ing lamp is turned on to indicate this condition to the driver.
LINE PRESSURE SWITCH
 With the transfer system design, cont rol of the oil pressure provides the transmission of drive torque to the
front wheels. The main pressure to control the oil pressure is referred to as the line pressure.
 The line pressure switch determines whether or not adequate line pressure has built up under different oper-
ating conditions.
 The line pressure switch closes when line pressure is produced.
 The line pressure switch senses line pressure abnormalities and turns the 4WD warning lamp ON.
CLUTCH PRESSURE SWITCH
 The clutch pressure switch determines whether or not adequate clutch pressure has built up under different
operating conditions.
 The clutch pressure switch closes when clutch pressure is produced.
 The clutch pressure switch senses clutch pressu re abnormalities and turns the 4WD warning lamp ON.
WAIT DETECTION SWITCH
 The wait detection switch operates when there is circulating torque produced in the propeller shaft (L→H) or
when there is a phase difference between 2-4 sleeve and clutch drum (H →L). After the release of the circu-
lating torque, the wait detection switch helps provi de the 4WD lock gear (clutch drum) shifts. A difference
may occur between the operation of the 4WD shift swit ch and actual drive mode. At this point, the wait
detection switch senses an actual drive mode.
 The wait detection switch operates as follows.
- 4WD lock gear (clutch drum) locked: ON
- 4WD lock gear (clutch drum) released: OFF
 The wait detection switch senses an actual drive mode and the 4WD shift indicator lamp indicates the vehi-
cle drive mode.
ATP SWITCH
ATP switch detects if transfer case is in neutral by the position of the L-H shift fork.
NOTE:
Transfer case may be in neutral when shifting between 4H-4LO.
NEUTRAL-4LO SWITCH
The neutral-4LO switch detects that tr ansfer gear is in neutral or 4LO (or shifting from neutral to 4LO) condi-
tion by L-H shift fork position.
Condition 4WD warning lamp
System normal OFF
Lamp check Turns ON when ignition switch is turned ON.
Turns OFF after engine start.
4WD system malfunction ON
During self-diagnosis Flashes malfunction mode.
Large difference in diameter of front/
rear tires Flashes slow (1 flash / 2 seconds)
(Continues to flash until the ignition switch is turned OFF)
High fluid temperature in transfer case Flashes rapidly (2 flashes / 1 second)
(Continues to flash until fluid temperature returns to normal)
Revision: December 20092009 QX56

4WD SYSTEMDLN-17
< FUNCTION DIAGNOSIS > [ATX14B]
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CAN CommunicationINFOID:0000000003772078
Refer to LAN-51, "DTC Index".
1. A: Transfer shut off relay E69
B: Transfer shift low relay E47
C: Transfer shift high relay E46 2. A: Actuator
B: Transfer control device F58
C: Actuator lever
D: Transfer case 3. Wait detection switch F59
(View with transfer case removed)
4. A: Clutch pressure switch B: Line pressure switch
C: Transfer fluid temperature sensor
D: 2-4WD shift solenoid valve
E: Clutch pressure solenoid valve
(View with contro l valve removed
from transfer case) 5. A: Neutral 4LO switch F60
B: ATP switch F55
C: Transfer motor F57
D: Transfer terminal cord assembly F56
E: Oil filter 6. Combination meter M23, M24
A: 4WD warning lamp
B: ATP warning lamp
C: 4LO indicator lamp (located in in-
formation display)
D: 4WD shift indicator lamp
7. 4WD shift switch M141 8. Transfer control unit E142, E143 9. A: Transfer dropping resistor E135 B: Transfer motor relay E153, E154
(View with battery removed)
Revision: December 20092009 QX56

DLN-18
< FUNCTION DIAGNOSIS >[ATX14B]
DIAGNOSIS SYSTEM (T
RANSFER CONTROL UNIT)
DIAGNOSIS SYSTEM (TRA NSFER CONTROL UNIT)
CONSULT-III Function (ALL MODE AWD/4WD)INFOID:0000000003772079
FUNCTION
CONSULT-III can display each diagnostic item us ing the diagnostic test modes shown following.
SELF-DIAG RESULT MODE
Operation Procedure
1. Connect CONSULT-III.
2. With engine at idle, touch SELF-DIAG RESULTS.
Display shows malfunction experienced since the last erasing operation.
NOTE:
The details for TIME are as follows:
 0: Error currently detected with transfer control unit.
 Except for 0: Error detected in the pa st and memorized with transfer control unit.
Detects frequency of driving after DTC occurs (frequency of turning ignition switch ON/OFF).
How to Erase Self-d iagnostic Results
1. Perform applicable inspection of malfunctioning item and then repair or replace.
2. Start engine and select SELF-DIAG RESULTS m ode for ALL MODE AWD/4WD with CONSULT-III.
3. Touch ERASE on CONSULT-III screen to erase DTC memory. CAUTION:
If memory cannot be erased, pe rform applicable diagnosis.
SELF-DIAGNOSTIC PROCEDURE (WITHOUT CONSULT-III)
Description
If the engine starts when there is a malfunction in the 4W D system, the 4WD warning lamp turns ON or flickers
in the combination meter. When the system functions properly, the warning lamp turns ON when the ignition
switch is turned to ON, and it turns OFF after engine starts . To locate the cause of a malfunction, start the self-
diagnosis function. The 4WD warning lamp in the co mbination meter will indicate the malfunction area by
flashing according to the self-diagnostic results. Refer to DLN-97, "DTC Index"
.
Diagnostic Procedure
1. Warn up engine.
2. Move A/T selector lever to P position.
3. Turn 4WD shift switch to 2WD position.
4. Turn ignition switch ON and OFF at least twice, and then turn ignition switch OFF.
5. Turn 4WD shift switch to AUTO position.
6. Turn ignition switch ON. (Do not start engine.)
7. 4WD warning lamp ON.
8. Move A/T selector lever to R position.
9. Turn 4WD shift switch to 2WD, AUTO and 2WD in order.
10. Move A/T selector lever to D position.
11. Turn 4WD shift switch to 4H, AUTO and 4H in order.
ALL MODE AWD/4WD diagnostic mode Description
SELF-DIAG RESULTS Displays transfer control unit self-diagnosis results.DATA MONITOR Displays transfer control unit input/output data in real time.
WORK SUPPORT Supports inspections and adjustments. Commands are transmitted to the transfer control
unit for setting the status suitable for required operation, input/output signals are received
from the transfer control unit and received data is displayed.
CAN DIAG SUPPORT MNTR The results of transmit/receive diagnosis of CAN communication can be read. ECU PART NUMBER Transfer control unit part number can be read.
Revision: December 20092009 QX56

DIAGNOSIS SYSTEM (TRANSFER CONTROL UNIT)
DLN-19
< FUNCTION DIAGNOSIS > [ATX14B]
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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: December 20092009 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 transmission range switch
status is displayed.
Signal input with CAN communication line.
R POSI SW AT [ON/OFF] ×–×R position signal of transmission range switch
status is displayed.
Signal input with CAN communication line.
P POSI SW AT [ON/OFF] ×–×P position signal of 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
output.
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: December 20092009 QX56

DIAGNOSIS SYSTEM (TRANSFER CONTROL UNIT)
DLN-21
< FUNCTION DIAGNOSIS > [ATX14B]
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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 c hanging 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 shaft revolution signal (output speed
sensor) 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: December 20092009 QX56

DLN-84
< ECU DIAGNOSIS >[ATX14B]
TRANSFER CONTROL UNIT
MOTOR RELAY MON
[ON/OFF]Check signal for transfer
control unit signal output  Accelerator pedal de-
pressed
 Vehicle stopped
 Engine running
 Brake pedal depressed 4WD shift switch: 2WD OFF
4WD shift switch: AUTO
or 4LO (A/T selector lever
P or N position)
OFF
(ON for approx. 2
sec. after shifting to P and N.)
4WD shift switch: AUTO
or 4LO (Except for A/T se-
lector lever P or N posi-
tion) ON
4WD shift switch: 4H (A/T
selector lever P position) OFF
(ON for approx. 2
sec. after shifting to P.)
4WD shift switch: 4H (Ex-
cept for A/T selector lever
P position) ON
4WD FAIL LAMP [ON/
OFF] Condition of 4WD warn-
ing lamp 4WD warning lamp: ON ON
4WD warning lamp: OFF OFF
2WD IND [ON/OFF] Condition of 4WD shift in-
dicator lamp (2WD indi-
cator lamp) 2WD indicator lamp of 4WD shift indicator lamp: OFF OFF
2WD indicator lamp of 4WD shift indicator lamp: ON ON
AUTO IND [ON/OFF] Condition of 4WD shift in-
dicator lamp
(AUTO indi-
cator lamp) AUTO indicator lamp of 4WD shift indicator lamp: OFF OFF
AUTO indicator lamp of 4WD shift indicator lamp: ON ON
LOCK IND [ON/OFF] Condition of 4WD shift in-
dicator lamp (Lock indi-
cator lamp) Lock indicator lamp of 4WD shift indicator lamp: OFF OFF
Lock indicator lamp of 4WD shift indicator lamp: ON ON
4L IND [ON/OFF] Condition of 4LO indica-
tor lamp condition 4LO indicator lamp: OFF OFF
4LO indicator lamp: ON ON
ATP IND [ON/OFF] Condition of ATP indica-
tor lamp ATP indicator lamp: ON ON
AT P i n d i c a t o r l a m p : O F F O F F
SHIFT POS SW1 [ON/
OFF] Condition of actuator po-
sition switch 1
(Low)  Vehicle stopped
 Engine running
 A/T selector lever N posi-
tion
 Brake pedal depressed 4WD shift switch: 4LO ON
4WD shift switch: 2WD,
AUTO or 4H
OFF
SHIFT POS SW2 [ON/
OFF] Condition of actuator po-
sition switch 2
(High)  Vehicle stopped
 Engine running
 A/T selector lever N posi-
tion
 Brake pedal depressed 4WD shift switch: 4H,
AUTO or 2WD
ON
4WD shift switch: 4LO OFF
SHIFT ACT1 [ON/OFF] Output condition to actu-
ator motor (High)  Vehicle stopped
 Engine running
 A/T selector lever N posi-
tion
 Brake pedal depressed
4WD shift switch: 4H to
4LO (Wait function is op-
erating.) ON
Except the above OFF
SHIFT AC MON1 [ON/
OFF] Check signal for transfer
control unit signal output  Vehicle stopped
 Engine running
 A/T selector lever N posi-
tion
 Brake pedal depressed 4WD shift switch: 4H to
4LO (Wait function is op-
erating.)
ON
Except the above OFF
SHIFT ACT2 [ON/OFF] Output condition to actu-
ator motor (Low)  Vehicle stopped
 Engine running
 A/T selector lever N posi-
tion
 Brake pedal depressed 4WD shift switch: 4LO to
4H (Wait function is oper-
ating.)
ON
Except the above OFF
Monitored item [Unit] Content Condition Display value
Revision: December 20092009 QX56