3B-21 Differential:
DTC C1251: Coupling Air Temperature Sensor Circuit Short
Wiring Diagram
[A]: 4WD control module connector "G26" (viewed from harness side)
1. Coupling air temperature sensor
DTC Detecting Condition and Trouble Area
DTC detecting condition
Input signal from coupling air temperature sensor is lower than
specified value.
DTC Confirmation Procedure
1) Clear DTC using scan tool.
2) Turn ignition switch to ON position for 10 seconds.
3) Check DTC.
Troubleshooting
Step
1
Was "4WD control system check" performed?
2
Coupling 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?
BRN
G26-25
1
ORN
G26-24
[A]
12
11
10
9
8
7
26
25
24
23
22
21
20
Action
2
5V
5
4
3
2
6
1
19
18
17
16
15
14
13
I7RW01320006-01
2. 4WD control module
• Coupling air temperature sensor
• Coupling air temperature sensor circuit
• 4WD control module
Yes
Go to Step 2.
Go to Step 3.
S7RW0A3204017
Trouble area
No
Go to "4WD Control
System Check".
Go to Step 5.