DESCRIPTION
If a malfunction in the power source circuit occurs and, when a malfunction in communication with the skid control ECU or in a speed sensor occurs, the 4WD control ECU will prohibit operations by the fail-safe function. Refer to DIAGNOSIS SYSTEM .
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1241/94 | When the following continues for 10 seconds or more: At a vehicle speed of 2 mph (3 km/h) or more, the voltage of IG1 terminal is 9.5 V or less. When both of the following continue for 60 seconds or more: With the voltage of IG1 terminal 9.5 V or less, communication with the skid control ECU cannot be performed. A malfunction in communication with the skid control ECU. | Battery ECU-IG LH fuse Wire harness (IG1 circuit, GND circuit) CAN communication system 4WD control ECU |
Scheme 143
If a malfunction in the speed sensor signal circuit occurs, the 4WD control ECU will output this DTC. When slip is detected based on signals sent from the 4 vehicle speed sensors, the 4WD control ECU controls torque distribution between front and rear wheels according to the amount of slip.
| DTC No. | DTC Detecting Condition | Trouble Area |
|---|---|---|
| C1296/96 | When the following continues for 30 seconds or more: At a vehicle speed of 6 mph (10 km/h) or more, an open or short in the speed sensor signal circuit occurs. When the following continues for 0.5 seconds or more: An open or short in the speed sensor signal circuit occurs. When the following continues for 5 seconds or more: At a vehicle speed of 12 mph (20 km/h) or more, noise occurs in the signal sent from the speed sensor at the abnormal wheel. While the vehicle is driving, momentary interruption in the speed sensor signal circuit occurs 255 times or more. | Brake control system (speed sensor circuit) Wire harness (Speed signal circuit) 4WD control ECU |
Scheme 144
- The 4WD control ECU determines that the vehicle is turning based on the signals sent from the steering angle sensor.
- The steering angle sensor signal is sent to the 4WD control ECU via CAN communication system.
- The 4WD control ECU detects the amount of steering wheel movement and performs "slip control at vehicle start up", according to the amount of movement, and "slip control" to secure high turning performance.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1297/97 | When the voltage of the 4WD control ECU IG1 terminal is 9.5 V or more, the steering angle sensor malfunction signal is received. | Steering angle sensor CAN communication system Brake control system |
Scheme 145
- The 4WD control ECU receives signals from each sensor to control clutch fluid pressure for limiting the center differential operation, which distributes torque according to the driving conditions.
| DTC No. | DTC Detecting Condition | Trouble Area |
|---|---|---|
| C1298/98 | When the following continues for 1 second or more: With the voltage of the IG1 terminal 9.5 V or more, an open or short in the linear solenoid circuit (transfer control solenoid) occurs. | Transfer transmission wire Wire harness Transfer control solenoid assembly 4WD control ECU |
Scheme 146
- If wheel slip continues, differential control will be disabled when the torque-distribution ratio of the differential clutch exceeds the set value and a malfunction in the output of the wheel speed sensors, etc. occurs.
- If a difference in diameter between the front and rear wheels is determined, differential control will be disabled.
| DTC No. | DTC Detecting Condition | Trouble Area |
|---|---|---|
| C1299/99 | When both of the following are detected: The torque-distribution ratio of the differential clutch exceeds the set value. The vehicle is driven with tires different in size between the front and rear. | Tire size 4WD control ECU |
- The 4WD control ECU inputs the signals sent from the ECM, skid control ECU, and steering angle sensor via the CAN communication system.
- When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.
| DTC No. | DTC Detecting Condition | Trouble Area |
|---|---|---|
| U0073/86 | When the following continues for 5 seconds or more: Signals from the 4WD control ECU are not received. When the following occurs 10 times consecutively: A communication malfunction (bus off) occurs one or more times within 0.1 second. | Wire harness (CANL, CANH circuit) 4WD control ECU |
| U0100/85 | When both of the following continue for 2 seconds or more: The voltage of the IG1 terminal is 10 V or more. At a vehicle speed of 38 mph (60 km/h) or more, communication with the ECM cannot be performed. | Wire harness (CANL, CANH circuit) 4WD control ECU ECM |
| U0122/83 | When both of the following continue for 3 seconds or more: The voltage of the IG1 terminal is 10 V or more. Communication with the skid control ECU cannot be performed. | Wire harness (CANL, CANH circuit) 4WD control ECU Skid control ECU |
| U0126/84 | When both of the following continue for 1 second or more: The voltage of the IG1 terminal is 10 V or more. Communication with the steering angle sensor cannot be performed. When all of the following occur 10 times consecutively: The voltage of the IG1 terminal is 10 V or more. The vehicle speed is 38 mph (60 km/h) or more. The condition that communication with the steering angle sensor cannot be performed occurs once within 5 seconds. | Wire harness (CANL, CANH circuit) 4WD control ECU Steering angle sensor |
The 4WD control ECU is connected to the combination meter assembly via CAN and Multiplex communications.
If any of the following is detected, the multi-information display indicates a malfunction in the four-wheel drive control system.
- There is a malfunction in the 4WD control ECU internal circuit.
- A low voltage is applied to the power source for the 4WD control ECU.
- There is a malfunction in the CAN communication system.
- There is a malfunction in the brake control system.
- During fail-safe function.
HINT
When any of the DTCs C1297/97, U0100/85, and U0126/84 is detected, the 4WD indicator light will not come on.
Scheme 147
Refer to 4WD Indicator Light Remains ON
Connecting terminals TC and CG of the DLC3 causes the 4WD control ECU to display a DTC on the multi-information display.
