DESCRIPTION
If a malfunction in the power source circuit occurs, or 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.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1241 | When the following continues for 10 seconds or more: At a vehicle speed of 2 mph (3 km/h) or more, the IG1 terminal voltage is 9.5 V or less. When either of the following is detected: With the IG1 terminal voltage 9.5 V or less, communication with the skid control ECU is impossible. Vehicle speed sensor voltage is reduced for 60 seconds or more. When the following continues for 3 seconds or more: The IG1 terminal voltage 17 V or more. | Battery ECU-IG1 No. 2 fuse Wire harness and connector (IG1 circuit, GND circuit) Brake control system CAN communication system 4WD control ECU |
Scheme 121
If a malfunction in the power source circuit occurs, or 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.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1241 | When the following continues for 10 seconds or more: At a vehicle speed of 2 mph (3 km/h) or more, the IG1 terminal voltage is 9.5 V or less. When either of the following is detected: With the IG1 terminal voltage 9.5 V or less, communication with the skid control ECU is impossible. Vehicle speed sensor voltage is reduced for 60 seconds or more. When the following continues for 3 seconds or more: The IG1 terminal voltage 17 V or more. | Battery ECU-IG1 No. 2 fuse Wire harness and connector (IG1 circuit, GND circuit) Brake control system CAN communication system 4WD control ECU |
If a malfunction in the ECM circuit occurs, the 4WD control ECU will output this DTC.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1280 | When the following continues for 5 seconds or more: - Communication with engine control ECM is operating normally, but SFI system is malfunctioning. | SFI system 4WD control ECU |
If a malfunction in the ECM circuit occurs, the 4WD control ECU will output this DTC.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1280 | When the following continues for 5 seconds or more: - Communication with engine control ECM is operating normally, but SFI system is malfunctioning. | SFI system 4WD control ECU |
If a malfunction in the speed sensor signal circuit deceleration sensor circuit occurs, the 4WD control ECU will output this DTC.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1296 | When one of the following condition is met: Wheel speed sensor malfunction is received from the skid control ECU Deceleration sensor malfunction is received from skid control ECU | Brake control system (speed sensor circuit) Brake control system (deceleration sensor circuit) Skid control ECU 4WD ECU |
If a malfunction in the speed sensor signal circuit deceleration sensor circuit occurs, the 4WD control ECU will output this DTC.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1296 | When one of the following condition is met: Wheel speed sensor malfunction is received from the skid control ECU Deceleration sensor malfunction is received from skid control ECU | Brake control system (speed sensor circuit) Brake control system (deceleration sensor circuit) Skid control ECU 4WD ECU |
- 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 the 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 | When voltage of 4WD control ECU IG terminal is 9.5 V or more, and steering angle sensor malfunction signal is received. | Steering angle sensor CAN communication 4WD control ECU Wire harness |
Scheme 122
- 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 the 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 | When voltage of 4WD control ECU IG terminal is 9.5 V or more, and steering angle sensor malfunction signal is received. | Steering angle sensor CAN communication 4WD control ECU Wire harness |
The 4WD control ECU receives signals from each sensor to control clutch pressure to distribute torque according to the driving conditions.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1298 | When the following continues for 1 second or more: - With the current of the 0.8 A or more, an open or short in the linear solenoid circuit occurs. | 4WD fuse Wire harness and connector Electromagnetic control coupling 4WD control ECU |
Scheme 123
The 4WD control ECU receives signals from each sensor to control clutch pressure to distribute torque according to the driving conditions.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| C1298 | When the following continues for 1 second or more: - With the current of the 0.8 A or more, an open or short in the linear solenoid circuit occurs. | 4WD fuse Wire harness and connector Electromagnetic control coupling 4WD control ECU |
- 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 Detection Condition | Trouble Area |
|---|---|---|
| C1299 | When one of the following conditions is met: - Condition that controls coupling calorific value is predefined value or more. - The estimated transfer oil temperature exceeds the specified value. - Vehicle is driven and energy load tire radius difference between front tires and rear tires is more than 3%. | Tire size Electromagnetic control coupling 4WD ECU |
- 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 Detection Condition | Trouble Area |
|---|---|---|
| C1299 | When one of the following conditions is met: - Condition that controls coupling calorific value is predefined value or more. - The estimated transfer oil temperature exceeds the specified value. - Vehicle is driven and energy load tire radius difference between front tires and rear tires is more than 3%. | Tire size Electromagnetic control coupling 4WD ECU |
- The 4WD ECU inputs the signals sent from the ECM and skid control ECU 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 Detection Condition | Trouble Area |
|---|---|---|
| U0073 | 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 seconds. | CAN communication system |
| U0100 | 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 60 km/h (38 mph) or more, communication with the ECM cannot be performed. | CAN communication system |
| U0129 | When the following continues 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. | CAN communication system |
- The 4WD ECU inputs the signals sent from the ECM and skid control ECU 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 Detection Condition | Trouble Area |
|---|---|---|
| U0073 | 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 seconds. | CAN communication system |
| U0100 | 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 60 km/h (38 mph) or more, communication with the ECM cannot be performed. | CAN communication system |
| U0129 | When the following continues 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. | CAN communication system |
The 4WD control ECU is connected to the combination meter via the CAN communication system.
If the 4WD control ECU stores any DTCs which are related to the active torque control 4WD system, the AWD warning light comes on in the combination meter.
Scheme 124
The 4WD control ECU is connected to the combination meter via the CAN communication system.
If the 4WD control ECU stores any DTCs which are related to the active torque control 4WD system, the AWD warning light comes on in the combination meter.
An AWD Lock Switch (4 Wheel Drive Control Switch) has been provided.
This enables the driver to select between the AUTO and LOCK modes by operating the switch.
The system optimally controls the torque distribution to the front and rear wheels in the respective modes.
Scheme 125
Scheme 126
Scheme 127
- INSPECT 4 WHEEL DRIVE CONTROL SWITCH Disconnect the connector of 4 wheel drive control switch. Refer to «REMOVAL». Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 6 (B) - 7 (GND) Press continuously 4 Wheel Drive Control Switch Below 1 ohms Release 4 Wheel Drive Control Switch 10 kohms or higher TEXT IN ILLUSTRATION *1 Component without harness connected (4 Wheel Drive Control Switch) NG --> See step 4 OK: Go to next step
- CHECK HARNESS AND CONNECTOR (4WD ECU - BODY GROUND) Connect the connector of 4 wheel drive control switch. Disconnect the ECU connector. Measure the resistance of the wire harness side connector. Standard Resistance Tester Connection Condition Specified Condition O2-2 (4WDL) - Body Ground Press continuously 4 Wheel Drive Control Switch Below 1 ohms Release 4 Wheel Drive Control Switch 10 kohms or higher TEXT IN ILLUSTRATION *1 Rear view of wire harness connector (to 4WD ECU) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 3
- REPLACE 4WD ECU ASSEMBLY. Refer to «REMOVAL»
- REPLACE 4 WHEEL DRIVE CONTROL SWITCH. Refer to «REMOVAL»
An AWD Lock Switch (4 Wheel Drive Control Switch) has been provided.
This enables the driver to select between the AUTO and LOCK modes by operating the switch.
The system optimally controls the torque distribution to the front and rear wheels in the respective modes.
See also:
• INSPECTION