Whenever vehicle is hoisted for any other service work than oil change, also be sure to check for oil leakage.
Coupling Description
Coupling is installed in the forward of rear differential. The road situation and driving are judged with 4WD control module based on information from sensor and each control module, and the distribution of driving force of the front and rear wheel has been changed by controlling the current to coupling. Coupling air temperature sensor is installed in coupling case and measures the temperature in coupling.
4WD system has three driving mode (2WD, 4WD-auto, 4WD-lock). The mode corresponding to the running situation can be selected by 2WD/4WD switch.
Scheme 1
Indicator Operation
The 4WD control module outputs operation signal of the 4WD AUTO indicator and the 4WD LOCK indicator. Indicators as follows in order to inform what state the 4WD control system is.
| Operation | Condition (when any one of the following conditions is satisfied) | |
|---|---|---|
| Indicator | ||
| 4WD AUTO indicator | OFF | Ignition switch is OFF. Vehicle is at "2WD" position or "4WD-lock" position. |
| ON | Within 2 seconds after ignition switch is turn ON (checking indicator operation). Vehicle is at "4WD-auto" position. 4WD control module detects DTC of 4WD control system. | |
| Blinking at intervals of 2 seconds continuously | 4WD control module detects the rotation difference of front wheel and rear wheel and/or temperature of transfer more than specified temperature. | |
| 4WD LOCK indicator | OFF | Ignition switch is OFF. Vehicle is at "2WD" position or "4WD-auto" position. |
| ON | Within 2 seconds after ignition switch is turn ON (checking indicator operation). Vehicle is at "4WD-lock" position. 4WD control module detects DTC of 4WD control system. | |
INDICATOR OPERATION TABLE
CAN Communication System Description
Refer to CAN COMMUNICATION SYSTEM DESCRIPTION for CAN communication system description.
When 4WD control module receive the signal of abnormal as following information, vehicle is not changed to 4WD-auto and 4WD-lock mode.
Scheme 2
Scheme 3
4WD Position Indicator Operation Check
- Turn ignition switch to OFF position.
- Check that 4WD position indicators turn on for about 2 seconds and then turns off. If any faulty condition is found, proceed to «4WD POSITION INDICATOR DOES NOT COME ON AT IGNITION SWITCH ON BUT ENGINE STOPS»(ref-268914-S14815998912007102700000) or «4WD POSITION INDICATOR REMAINS ON STEADY AT IGNITION SWITCH ON»(ref-268914-S20704364212007102700000) .
4WD Control System Operation Inspection
Note. It automatically changes into "4WD-auto" position, when the vehicle speed becomes specified speed or more at "4WD-lock" position. It is "4WD-auto" position until switch will be selected to "4WD-lock" position at next time. When ABS operates while changed of each position, it is discontinued of change. End of the ABS operation, and then returned to the position of before.
- Inspect switch operation from "4WD-auto" to "2WD" as follows. Start engine. Push 2WD/4WD switch to "2WD" position. Check that 4WD AUTO indicator and 4WD LOCK indicator not come ON.
- Inspect switch operation from "2WD" to "4WD-auto" as follows. Start engine. Push 2WD/4WD switch to "AUTO" position. Check that 4WD AUTO indicator comes ON steady and 4WD LOCK indicator not come ON.
- Inspect switch operation from "4WD-auto" to "4WD-lock" as follows. Start engine. Push 2WD/4WD switch to "LOCK" position, and keep it for 3 seconds or more. Check that 4WD AUTO indicator not come ON and 4WD LOCK indicator comes ON steady.
- Inspect switch operation from "4WD-lock" to "4WD-auto" as follows. Start engine. Push 2WD/4WD switch to "AUTO" position. Check that 4WD AUTO indicator comes ON steady and 4WD LOCK indicator not come ON.