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TF-82
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
DIAGNOSTIC PROCEDURE
1. CHECK POWER SUPPLY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Connect transfer control unit harness connector.
3. Check voltage between transfer control unit harness connector
terminal and ground.
4. Turn ignition switch “ON”. (Do not start engine.)
5. Check voltage between transfer control unit harness connector
terminals and ground.
OK or NG
OK >> GO TO 2.
NG >> Check the following. If any items are damaged, repair or
replace damaged parts.
10A fuse No. 26 located in the fuse and fusible link box. Refer to PG-4, "POWER SUPPLY
ROUTING CIRCUIT" .
Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 1 (G).
Harness for short or open between transfer shut off relay harness connector E69 terminal 2
(SB) and transfer control unit harness connector E143 terminal 30 (SB).
Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 3 (G).
Harness for short or open between transfer shut off relay harness connector E69 terminal 5 (Y/
R) and transfer control unit harness connector E142 terminal 22 (Y/R).
Transfer shut off relay. Refer to TF-57, "COMPONENT INSPECTION" .
Connector Terminal (Wire color) Voltage (Approx.)
E14216 (Y/R) - Ground
0V
22 (Y/R) - Ground
E143 30 (SB) - Ground Battery voltage
SDIA2834E
Connector Terminal (Wire color) Voltage (Approx.)
E14216 (Y/R) - Ground
Battery voltage
22 (Y/R) - Ground
E143 30 (SB) - Ground 0V
SDIA2835E
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TROUBLE DIAGNOSIS FOR SYSTEM
TF-83
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Revision: October 20052005 QX56
2. CHECK GROUND CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connec-
tor E142 terminals 3 (B), 6 (B), E143 terminal 45 (B) and ground.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
3. CHECK ACTUATOR MOTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay. Refer to TF-22, "
Location of Electrical Parts" .
3. Check voltage between transfer shift high relay harness connec-
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
4. Turn ignition switch “ON”. (Do not start engine.)
5. Check voltage between transfer shift high relay harness connec-
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
OK or NG
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or
replace damaged parts.
20A fuse No. 57 located in the fuse and relay box. Refer to PG-4, "POWER SUPPLY ROUTING
CIRCUIT" .
Harness for short or open between battery, transfer shift high relay harness connector E46 ter-
minal 5 (R) and transfer shift low relay harness connector E47 terminal 5 (R). Continuity should exist.
SDIA2691E
Connector Terminal (Wire color) Voltage (Approx.)
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground
SDIA2707E
Connector Terminal (Wire color) Voltage (Approx.)
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground
SDIA2706E
Page 3227 of 3419

TF-84
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
4. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND TRANSFER SHIFT RELAY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and transfer control device (actuator motor) harness
connector.
3. Remove transfer shift high relay and transfer shift low relay. Refer to TF-22, "
Location of Electrical Parts" .
4. Check continuity between the following terminals.
–Transfer control unit harness connector E143 terminal 33 (R/L)
and transfer shift high relay harness connector E46 terminal 3
(R/L).
–Transfer control unit harness connector E143 terminal 42 (P/G)
and transfer shift low relay harness connector E47 terminal 3 (P/
G).
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
5. CHECK TRANSFER SHIFT RELAY GROUND CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay.
3. Check continuity between transfer shift high relay harness con-
nector E46 terminals 1 (B/W), 4 (B), transfer shift low relay har-
ness connector E47 terminal 1 (B/W), 4 (B) and ground.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
6. 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-1 >> With CONSULT-II: GO TO 7.
OK-2 >> Without CONSULT-II: GO TO 8.
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. Continuity should exist.
SDIA2712E
Continuity should exist.
SDIA2708E
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TROUBLE DIAGNOSIS FOR SYSTEM
TF-85
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Revision: October 20052005 QX56
7. PERFORM SELF-DIAGNOSIS (WITH CONSULT-II)
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE”.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Perform the self-diagnosis again.
Is the
“SHIFT ACT CIR [P1819]” displayed?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.
8. PERFORM SELF-DIAGNOSIS (WITHOUT CONSULT-II)
Without CONSULT-II
1. Perform the self-diagnosis and then erase self-diagnostic results. Refer to TF-50, "
SELF-DIAGNOSTIC
PROCEDURE (WITHOUT CONSULT-II)" and TF-53, "ERASE SELF-DIAGNOSIS" .
2. Perform the self-diagnosis again.
Do the self-diagnostic results indicate transfer control device?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.
Engine Speed Signal (ECM)EDS0 02 IF
DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH ECM
Perform self-diagnosis with ECM. Refer to EC-130, "
SELF-DIAG RESULTS MODE" .
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 TF-36, "
Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 3.
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.
3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ECM again. Refer to EC-130, "
SELF-DIAG RESULTS MODE" .
Page 3229 of 3419

TF-86
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
Clutch Pressure SolenoidEDS002IG
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 Content Condition Display value
DUTY SOLENOID [%]Condition of clutch pres-
sure solenoid
Vehicle stopped
Engine running
A/T selector lever “N”
position
Brake pedal depressed4WD shift switch: 2WD 4%
4WD shift switch: AUTO 96 - 4%
4WD shift switch: 4H or
4LO4%
Te r m i n a lWire
colorItem Condition Data (Approx.)
10 L/W Transfer dropping resistor
Vehicle stopped
Engine running
A/T selector
lever “N” position
Brake pedal
depressed4WD shift switch: AUTO 4 - 14V
4WD shift switch: 2WD, 4H or 4LO Less than 1V
19 LClutch pressure solenoid
valve
Vehicle stopped
Engine running
A/T selector
lever “N” position
Brake pedal
depressed4WD shift switch: AUTO 1.5 - 3V
4WD shift switch: 2WD, 4H or 4LO Less than 1V
Page 3230 of 3419

TROUBLE DIAGNOSIS FOR SYSTEM
TF-87
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Revision: October 20052005 QX56
DIAGNOSTIC PROCEDURE
1. CHECK CLUTCH PRESSURE SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “DUTY SOLENOID”.
Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
OK or NG
OK >> GO TO 7.
NG >> GO TO 2.
Condition Display value
Vehicle stopped
Engine running
A/T selector lever “N” position
Brake pedal depressed4WD shift switch: 2WD 4%
4WD shift switch: AUTO 96 - 4%
4WD shift switch: 4H or
4LO4%
SDIA2718E
ConnectorTe r m i n a l
(Wire
color)ConditionVoltage
(Approx.)
E142 10 (L/W)
- Ground
Vehicle stopped
Engine running
A/T selector lever
“N” position
Brake pedal
depressed4WD shift switch:
AUTO4 - 14V
4WD shift switch:
2WD, 4H or 4LOLess
than 1V
19 (L) -
Ground
Vehicle stopped
Engine running
A/T selector lever
“N” position
Brake pedal
depressed4WD shift switch:
AUTO1.5 - 3V
4WD shift switch:
2WD, 4H or 4LOLess
than 1V
SDIA2719E
Page 3231 of 3419

TF-88
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND CLUTCH PRESSURE SOLENOID
VA LV E
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector, transfer terminal cord assembly harness connector
and transfer dropping resistor.
3. Check continuity between transfer control unit harness connec-
tor E142 terminal 19 (L) and transfer terminal cord assembly
harness connector F56 terminal 6 (L).
4. Check continuity between transfer dropping resistor harness
connector E135 terminal 2 (L) and transfer terminal cord assem-
bly harness connector F56 terminal 6 (L).
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND TRANSFER DROPPING RESISTOR
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and transfer dropping resistor harness connector.
3. Check continuity between transfer control unit harness connec-
tor E142 terminal 10 (L/W) and transfer dropping resistor har-
ness connector E135 terminal 1 (L/W).
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.Continuity should exist.
SDIA2720E
Continuity should exist.
SDIA2721E
Continuity should exist.
SDIA2722E
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TROUBLE DIAGNOSIS FOR SYSTEM
TF-89
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Revision: October 20052005 QX56
4. CHECK GROUND CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check continuity between transfer terminal cord assembly har-
ness connector F56 terminal 19 (B) and ground.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
5. CHECK 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.
OK or NG
OK >> GO TO 6.
NG >> Replace clutch pressure solenoid. Refer to TF-22,
"Location of Electrical Parts" .
6. CHECK TRANSFER DROPPING RESISTOR
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer dropping resistor harness connector. Refer to TF-22, "
Location of Electrical Parts" .
3. Check resistance between transfer dropping resistor terminals 1
and 2.
OK or NG
OK >> GO TO 7.
NG >> Replace transfer dropping resistor. Refer to TF-22,
"Location of Electrical Parts" .
7. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-36, "
Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 8.
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. Continuity should exist.
SDIA2723E
6 - 19 : Approx. 3.0 - 3.4 Ω
WDIA0225E
1 - 2 : Approx. 11.2 - 12.8 Ω
SDIA2725E