
Downloaded from www.Manualslib.com manuals search engine 3B-17 Differential:
DTC C1240: 4WD Control Module Power Supply Circuit MalfunctionS6RW0D3204015
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Turn ignition switch to ON position for 10 seconds.
3) Check DTC.
Troubleshooting
[A]: 4WD control module connector “G26” (viewed from harness side) 3. “4WD” fuse
1. 4WD control module 4. Main fuse box
2. “IG COIL” fuse
DTC detecting condition Trouble area
4WD control module power supply voltage is out of specification. 4WD control module power supply circuit
5V
5V
G26-12
G26-11
G26-10BLK
WHT/RED
RED/BLK
1
2
3
4
YEL
1 2 3
4 5
6 7 8 9 10 11
12
13
14 15 16
17 18 19
20
21 22
23
24 25 26
[A]
I7RW01320005-01
Step Action Yes No
1Was “4WD control system check” performed?Go to Step 2. Go to “4WD Control
System Check”.
24WD control module power circuit check
1) Disconnect 4WD control module connector with ignition
switch OFF.
2) Check for proper connection to “G26” terminal of 4WD
control module connector.
3) If connection is OK, measure voltage between “G26-11”
terminal of 4WD control module connector and vehicle
body ground with ignition switch ON.
Is it 10 – 14 V?Poor “G26-11”
connection or
intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”. If wire and
connections are OK,
substitute a known-
good 4WD control
module and recheck.“4WD” fuse blown,
“WHT/RED” or “YEL”
wire is circuit open or
circuit short.

Downloaded from www.Manualslib.com manuals search engine Differential: 3B-18
DTC C1243: Internal Circuit Malfunction of 4WD Control ModuleS6RW0D3204016
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Start engine and run it for 10 seconds. or more.
3) Stop vehicle and check DTC.
Troubleshooting
Substitute a known-good 4WD control module and recheck.3Ground circuit check
1) Turn ignition switch to OFF position.
2) Check for proper connection to “G26-10” terminal of
4WD control module connector.
3) If OK, measure resistance between “G26-10” terminal of
4WD control module connector and vehicle body
ground.
If resistance 1
Ω or less?Substitute a known-
good 4WD control
module and recheck.Repair ground circuit. Step Action Yes No
DTC detecting condition Trouble area
Internal power supply malfunction of 4WD control module 4WD control module

Downloaded from www.Manualslib.com manuals search engine 3B-19 Differential:
DTC C1250: Coupling Air Temperature Sensor Circuit OpenS6RW0D3204017
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Turn ignition switch to ON position for 10 seconds.
3) Check DTC.
[A]: 4WD control module connector “G26” (viewed from harness side) 2. 4WD control module
1. Coupling air temperature sensor
DTC detecting condition Trouble area
Input signal from coupling air temperature sensor is higher than
specified value.• Coupling air temperature sensor
• Coupling air temperature sensor circuit
• 4WD control module
2
G26-25
G26-24ORN
BRN
5V
1
1 2 3
4 5
6 7 8 9 10 11
12
13
14 15 16
17 18 19
20
21 22
23
24 25 26
[A]
I7RW01320006-01

Downloaded from www.Manualslib.com manuals search engine 3B-21 Differential:
DTC C1251: Coupling Air Temperature Sensor Circuit ShortS6RW0D3204018
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Turn ignition switch to ON position for 10 seconds.
3) Check DTC.
Troubleshooting
[A]: 4WD control module connector “G26” (viewed from harness side) 2. 4WD control module
1. Coupling air temperature sensor
DTC detecting condition Trouble area
Input signal from coupling air temperature sensor is lower than
specified value.• Coupling air temperature sensor
• Coupling air temperature sensor circuit
• 4WD control module
2
G26-25
G26-24ORN
BRN
5V
1
1 2 3
4 5
6 7 8 9 10 11
12
13
14 15 16
17 18 19
20
21 22
23
24 25 26
[A]
I7RW01320006-01
Step Action Yes No
1Was “4WD control system check” performed?Go to Step 2. Go to “4WD Control
System Check”.
2Coupling air temperature sensor circuit check
1) Disconnect connector from coupling air temperature
sensor with ignition switch turned OFF.
2) Check for proper connection to “BRN” and “ORN”
terminals of coupling air temperature sensor connector.
3) If connection is OK, measure voltage between “BRN”
terminal of coupling air temperature sensor connector
and vehicle body ground with ignition switch turned ON.
Is it 4 – 6 V?Go to Step 3. Go to Step 5.

Downloaded from www.Manualslib.com manuals search engine 3B-23 Differential:
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Start engine and select 2WD/4WD switch to “LOCK” position.
3) Keep engine running at 2000 rpm for 10 seconds. or more.
4) Stop engine and check DTC.
Troubleshooting
Step Action Yes No
1Was “4WD control system check” performed?Go to Step 2. Go to “4WD Control
System Check”.
2Coupling assembly circuit check
1) Disconnect coupling assembly connector “L102” with
ignition switch turned OFF.
2) Check for proper connection to “L102-1” and “L102-4”
terminals of coupling assembly connector.
3) If connection is OK, measure voltage between “L102-1”
terminal of coupling assembly connector and vehicle
body ground.
Is it 10 – 14 V?Go to Step 3. Go to Step 6.
3Coupling assembly ground circuit check
1) Measure resistance between “L102-4” terminal of
coupling assembly connector and vehicle body ground
with ignition switch turned OFF.
Is resistance below 5
Ω?Go to Step 4. Go to Step 5.
4Coupling assembly check
1) Check coupling assembly referring to “Coupling
Assembly Inspection”.
Is it in good condition?Substitute a known-
good 4WD control
module and recheck.Replace coupling
assembly.
5Coupling assembly circuit check
1) Disconnect connector from 4WD control module
connector “G26” with ignition switch turned OFF.
2) Check for proper connection to “G26-2” and “G26-3”
terminals of 4WD control module connector.
3) If connection is OK, measure resistance between “G26-
2” terminal of 4WD control module connector and
vehicle body ground.
Is resistance below 5
Ω?“YEL” wire is open or
high resistance circuit.Substitute a known-
good 4WD control
module and recheck.
6Coupling assembly circuit check
1) Disconnect connector from 4WD control module
connector “G26” with ignition switch turned OFF.
2) Check for proper connection to “G26-3” terminal of 4WD
control module connector.
3) If connection is OK, measure resistance between “G26-
3” terminal of 4WD control module connector and “L102-
1” terminal of coupling assembly connector.
Is resistance below 5
Ω?Substitute a known-
good 4WD control
module and recheck.“GRY” wire is open or
high resistance circuit.

Downloaded from www.Manualslib.com manuals search engine Differential: 3B-24
DTC C1253: Coupling Assembly Circuit ShortS6RW0D3204020
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Start engine and select 2WD/4WD switch to “LOCK” position.
3) Keep engine running at 2000 rpm for 10 seconds. or more.
4) Stop engine and check DTC.
Troubleshooting
12V
G26-3
YEL GRY
G26-2
L102-1
L102-4 12
1 2 3
4 5
6 7 8 9 10 11
12
13
14 15 16
17 18 19
20
21 22
23
24 25 26
[A]
21
[B]
I7RW01320007-01
[A]: 4WD control module connector “G26” (viewed from harness side) 1. Coupling assembly
[B]: Coupling assembly connector “L102” (viewed from harness side) 2. 4WD control module
DTC detecting condition Trouble area
2WD/4WD switch is changed of 4WD lock position, and then
vehicle is not changed for more than 5 seconds.• Coupling assembly
• Coupling assembly circuit
• 4WD control module
Step Action Yes No
1Was “4WD control system check” performed?Go to Step 2. Go to “4WD Control
System Check”.
2Coupling assembly circuit check
1) Disconnect coupling assembly connector “L102” with
ignition switch turned OFF.
2) Check for proper connection to “L102-1” and “L102-4”
terminals of coupling assembly connector.
3) If connection is OK, measure voltage between “L102-1”
terminal of coupling assembly connector and vehicle
body ground.
Is it 10 – 14 V?Go to Step 3. Go to Step 6.
3Coupling assembly ground circuit check
1) Measure resistance between “L102-4” terminal of
coupling assembly connector and vehicle body ground
with ignition switch turned OFF.
Is resistance below 5
Ω?Go to Step 4. Go to Step 5.

Downloaded from www.Manualslib.com manuals search engine Differential: 3B-26
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Select 2WD/4WD switch to “2WD” position and keep its position for 10 seconds. Similarly select 2WD/4WD switch
to “AUTO” and “LOCK” position.
3) Check DTC.
TroubleshootingDTC detecting condition Trouble area
2WD/4WD switch combination different from specification is
detected for more than 5 seconds.• 2WD/4WD switch
• 2WD/4WD switch circuit
• 4WD control module
Step Action Yes No
1Was “4WD control system check” performed?Go to Step 2. Go to “4WD Control
System Check”.
22WD/4WD switch circuit check
1) Disconnect 2WD/4WD switch connector “L174” with
ignition switch turned OFF.
2) Check for proper connection to “L174-1” and “L174-5”
terminals of 2WD/4WD switch connector.
3) If connection is OK, measure voltage between “L174-1”
terminal or “L174-5” terminal of 2WD/4WD switch
connector and vehicle body ground.
Is it 10 – 14 V?Go to Step 3. Go to Step 5.
32WD/4WD switch ground circuit check
1) Measure resistance between “L174-4” terminal of 2WD/
4WD switch connector and vehicle body ground with
ignition switch turned OFF.
Is resistance below 5
Ω?Go to Step 4. “BLK/ORN” wire is
shorted to ground.
42WD/4WD switch check
1) Check 2WD/4WD switch referring to “2WD/4WD Switch
Inspection”.
Is it in good condition?Substitute a known-
good 4WD control
module and recheck.Replace 2WD/4WD
switch.
52WD/4WD switch circuit check
1) Disconnect connector from 4WD control module
connector “G26” with ignition switch turned OFF.
2) Check for shorted to ground in related circuits.
• Between “G26-13” terminal of 4WD control module
connector and “L174-1” terminal of 2WD/4WD switch
connector.
• Between “G26-14” terminal of 4WD control module
connector and “L174-5” terminal of 2WD/4WD switch
connector.
Are they in good condition?Substitute a known-
good 4WD control
module and recheck.Repair circuit.

Downloaded from www.Manualslib.com manuals search engine 3B-27 Differential:
DTC U0073: Control Module Communication Bus OffS6RW0D3204022
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
DTC U0100: Lost Communication with ECMS6RW0D3204023
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
DTC U0121: Lost Communication with ABS / ESP® Control ModuleS6RW0D3204024
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
DTC U0155: Lost Communication with Instrument Panel Cluster (IPC) Control ModuleS6RW0D3204025
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
Inspection of 4WD Control Module and Its CircuitsS6RW0D3204026
4WD control module and its circuits can be checked at coupler connected to 4WD control module by measuring
voltage, pulse signal.
CAUTION!
4WD control module cannot be checked by itself. It is strictly prohibited to connect voltmeter or
ohmmeter to 4WD control module with couplers disconnected from it.
Voltage and Signal Check
1) Check voltage using voltmeter (1) connected to each terminal of couplers.
2) Check signal using oscilloscope (2) connected to each terminal of couplers.
NOTE
• As each terminal voltage is affected by the battery voltage, confirm that it is 11 V or more when
ignition switch is turned ON.
• Pulse signal cannot be measured by voltmeter. It can be measured by oscilloscope.
• Item with asterisk (*) in normal voltage column can be read only by oscilloscope.
12
I4JA01332053-01