TF-90
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 QX56
8. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "
Removal and Installation" .
COMPONENT INSPECTION
Clutch Pressure Solenoid
1. Turn ignition switch “ OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter- minals 6 and 19.
4. If NG, replace clutch pressure solenoid. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
Transfer Dropping Resistor
1. Turn ignition switch “ OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer dropping resistor harness connector.
3. Check resistance between transfer dropping resistor terminals 1 and 2.
4. If NG, replace transfer dropping resistor. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
6 - 19 : Approx. 3.0 - 3.4
\b
WDIA0225E
1 - 2 : Approx. 11.2 - 12.8 \b
SDIA2725E
TROUBLE DIAGNOSIS FOR SYSTEMTF-105
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Revision: November 2009 2006 QX56
Clutch Pressure SwitchEDS002IK
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Data are reference value.
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.Monitored item [Unit]
Content ConditionDisplay value
CL PRES SW [ON /
OFF] Condition of clutch pres-
sure switch
Vehicle stopped
Engine running
A/T selector lever “
D” position
4WD shift switch: AUTO or 4H ( “Wait ” function is not
operating.) ON
Vehicle stopped
Engine running
4WD shift switch: 2WD (
“Wait ” function is not oper-
ating.) OFF
Terminal
Wire
color Item
ConditionData (Approx.)
34 BR Clutch pressure switch
Vehicle stopped
Engine running
A/T selector
lever “D ” position 4WD shift switch: AUTO or 4H (
“Wait ”
function is not operating.) 0V
Vehicle stopped
Engine running4WD shift switch: 2WD (
“Wait ” function is
not operating.) Battery voltage
TF-106
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 QX56
DIAGNOSTIC PROCEDURE
1. CHECK CLUTCH PRESSURE SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR ” mode for “ALL MODE AWD/4WD ” with CONSULT-II.
3. Read out ON/OFF switching action of the “CL PRES SW ” while
operating 4WD shift switch.
Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector terminals and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND CLUTCH PRESSURE SWITCH
1. Turn ignition switch “ OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the transfer terminal cord assembly harness con- nector.
3. Check continuity between transfer control unit harness connec- tor E143 terminal 34 and transfer terminal cord assembly har-
ness connector F56 terminal 7
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
Condition Display value
Ignition switch: ON
A/T selector lever “D ”
position 4WD shift switch: AUTO or 4H
(
“ Wait ” function is not operating.) ON
Ignition switch: ON 4WD shift switch: 2WD (
“Wait ”
function is not operating.) OFF
Connector Terminal ConditionVoltage
(Approx.)
E143 34 -
Ground
Ignition switch: ON
A/T selector lever
“ D ” position 4WD shift switch:
AUTO or 4H
(
“ Wait ” function is
not operating.) 0V
Ignition switch: ON 4WD shift switch:
2WD (
“Wait ” func-
tion is not operat-
ing.) Battery
voltage
WDIA0141E
SDIA2746E
Continuity should exist.
SDIA2747E
TROUBLE DIAGNOSIS FOR SYSTEMTF-107
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Revision: November 2009 2006 QX56
3. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-54, "
TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 4.
NG >> Check transfer control unit pin terminals for damage or loose connection with the harness connec- tor. If any items are damaged, repair or replace damaged parts.
4. CHECK CLUTCH PRESSURE SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove clutch pressure switch. Refer to TF-22, "
Location of Electrical Parts" .
3. Push and release clutch pressure switch and check continuity between transfer terminal cord assembly terminal 7 and ground.
OK or NG
OK >> GO TO 5.
NG >> Replace clutch pressure switch. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
5. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> GO TO 6.
NG >> Replace transfer control unit. Refer to TF-132, "
Removal and Installation" .
6. CRUISE TEST
Perform cruise test. Refer to TF-33, "
CRUISE TEST" .
OK or NG
OK >> Inspection End.
NG >> Perform the applicable trouble diagnosis.
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove clutch pressure switch. Refer to TF-22, "
Location of Electrical Parts" .
3. Push and release clutch pressure switch and check continuity between transfer terminal cord assembly terminal 7 and ground.
4. If NG, replace the clutch pressure switch. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
TerminalCondition Continuity
7 -
Ground Push clutch pressure switch
Yes
Release clutch pressure switch No
WDIA0171E
TerminalCondition Continuity
7 - Ground Push clutch pressure switch
Yes
Release clutch pressure switch No
WDIA0171E
TROUBLE DIAGNOSIS FOR SYMPTOMSTF-129
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Revision: November 2009 2006 QX56
5. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "
Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> Inspection End.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
4WD Warning Lamp Flashes SlowlyEDS002HS
SYMPTOM:
While driving, 4WD warning lamp flashes slowly. (When continuing to flash until turning ignition
switch OFF.)
NOTE:
Slow flashing: 1 time/2 seconds
DIAGNOSTIC PROCEDURE
1. CHECK TIRE
Check the following.
Tire pressure
Wear condition
Longitudinal tire size (There is no difference between longitudinal tires.)
OK or NG
OK >> GO TO 2.
NG >> Repair or replace damaged parts.
2. CHECK TRANSFER FLUID TEMPERATURE
Perform trouble diagnosis for transfer fluid temperature system. Refer to TF-102, "
Transfer Fluid Temperature"
.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK CLUTCH PRESSURE SWITCH
Perform trouble diagnosis for clutch pressure switch system. Refer to TF-105, "
Clutch Pressure Switch" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 5.
5. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "
Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> Inspection End.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
TF-130
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: November 20092006 QX56
Heavy Tight-corner Braking Symptom OccursEDS002HT
SYMPTOM:
Heavy tight-corner braking symptom occurs when vehicle is driven in AUTO mode and steering wheel
is turned fully to either side.
DIAGNOSTIC PROCEDURE
NOTE:
Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode. This is not
a malfunction.
Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions: 4WD shift
switch is "4H" or "4LO", steering wheel is turned fully to either side.
1. CHECK SYSTEM FOR CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to TF-50, "
SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)" .
Is "CAN COMM CIRCUIT [U1000]" displayed?
YES >> Perform trouble diagnosis for CAN communication line. Refer to TF-113, "CAN Communication
Line" .
NO >> GO TO 2.
2. CHECK SYSTEM FOR 4WD SHIFT SWITCH
Perform trouble diagnosis for 4WD shift switch system. Refer to TF-62, "
4WD Shift Switch" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK ACCELERATOR PEDAL POSITION SIGNAL CIRCUIT
Perform self diagnosis for ECM. Refer to EC-49, "
Emission-related Diagnostic Information" .
Is any malfunction deteced by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 4.
4. CHECK SYSTEM FOR CLUTCH PRESSURE SOLENOID
Perform trouble diagnosis for clutch pressure solenoid system. Refer to TF-105, "
Clutch Pressure Switch" .
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
5. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 6.
6. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "
Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 7.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
TROUBLE DIAGNOSIS FOR SYMPTOMSTF-131
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Revision: November 2009 2006 QX56
7. CHECK TRANSFER INNER PARTS
1. Disassemble transfer assembly. Refer to TF-146, "
Disassembly and Assembly" .
2. Check transfer inner parts.
OK or NG
OK >> Inspection End.
NG >> Repair or replace damaged parts.
4WD System Does Not OperateEDS002HU
SYMPTOM:
The vehicle cannot be put into 4WD mode. (Hydraulic system failure)
DIAGNOSTIC PROCEDURE
1. CHECK SYSTEM FOR 4WD SHIFT SWITCH
Perform trouble diagnosis for 4WD shift switch system. Refer to TF-62, "
4WD Shift Switch" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace damaged parts.
2. CHECK SYSTEM FOR CLUTCH PRESSURE SWITCH
Perform trouble diagnosis for clutch pressure switch system. Refer to TF-105, "
Clutch Pressure Switch" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 4.
4. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "
Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 5.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
5. CHECK TRANSFER INNER PARTS
1. Disassemble transfer assembly. Refer to TF-146, "
Disassembly and Assembly" .
2. Check transfer inner parts.
OK or NG
OK >> Inspection End.
NG >> Repair or replace damaged parts.
TF-146
TRANSFER ASSEMBLY
Revision: November 20092006 QX56
Disassembly and AssemblyEDS003BG
COMPONENTS
1. 2-4 sleeve2. L-H sleeve 3. Snap ring
4. Internal gear 5. Planetary carrier assembly 6. Metal bushing
7. Needle bearing 8. Sun gear 9. Carrier bearing
10. Snap ring 11. Snap ring 12. Input bearing
13. Wait detection switch 14. Check plug 15. Check spring
16. Check ball 17. Front case 18. Snap ring
19. Input oil seal 20. Shift cross 21. Side oil seal
22. Lock pin 23. Shift lever 24. Gasket
25. Drain plug 26. Front oil seal 27. Companion flange
28. Self-lock nut 29. Mainshaft 30. Needle bearing
31. Front bearing 32. Front drive shaft 33. Rear bearing
34. Spacer 35. Drive chain 36. Clutch drum
37. Snap ring 38. Clutch hub 39. Snap ring
40. Retaining plate 41. Driven plate (10 sheet) 42. Drive plate (10 sheet)
43. Return spring assembly 44. Press flange 45. Thrust needle bearing
46. Snap ring 47. Retaining pin 48. L-H fork
WDIA0194E