4WD Coupling Assembly: Other Hyundai Tucson II

Four Wheel Drive (4WD) Transfer Mode Selection

1. AUTO MODE: When driving in 4WD AUTO mode, the vehicle operates similar to conventional 2WD vehicles under normal operating conditions. However, if the system determines that there is a need for the 4WD mode, the engine's driving power is distributed to all four wheels automatically without driver intervention. When driving on normal roads and pavement, the vehicle moves similar to conventional 2WD vehicles.
2. LOCK MODE: This mode is used for climbing or descending sharp grades, off-road driving, driving on sandy and muddy roads, etc., to maximize traction. This mode automatically begins to deactivate at speeds above 30 km/h (19 mph) and is shifted to 4WD AUTO mode at speed above 40 km/h (25 mph). If the vehicle speed decelerates to below 30 km/h (19 mph), however, the transfer mode is shifted into 4WD LOCK mode again.

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1. Cruising (Auto Mode) Power is delivered mostly to the front wheels.
2. Cornering (Auto Mode) Adjusts the amount of power to the rear wheels based on the turning radius and cornering speed.
3. Wheel Slip (Auto Mode) If one or both of the front wheels lose traction, the system transfers an appropriate amount of power to the rear wheels based on the slip amount at the front wheels.
4. Lock Mode Maximizes rough terrain performance (active only at speeds below 40 km/h).

Electronic Coupling

Inactive

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Active

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Operation Order

1. 4WD ECU receives CAN signals from the vehicle's sensors.
2. 4WD ECU calculates the necessary amount of rear-wheel torque and sends the corresponding driving current to the actuator (electronic motor and hydraulic pump).
3. Hydraulic pressure generated by the actuator moves the piston.
4. Friction from the piston's movement engages the clutch.
5. Power is delivered to the rear wheels.

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Measure the resistance of pressure sensor

1. Turn ignition switch OFF.
2. Disconnect the pressure sensor connector.
3. Measure resistance between sensor terminal and terminal.
4. Check the measured resistance. (Refer to «PRESSURE SENSOR RESISTANCE»(ref-583729-S00070939092013112500000) table). PRESSURE SENSOR RESISTANCE Terminal Resistance - k/ohms PIN 2 - PIN 3 2.755 ~ 4.133 PIN 1 - PIN 3 1.892 ~ 2.838 PIN 1 - PIN 2 1.714 ~ 2.838

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1. Remove the coupling assembly. Refer to «REMOVAL»(ref-583729-S14830129542013112500000) .
2. Remove the extension Cable (A).
3. Remove the pressure sensor (A) with 24 mm socket. CAUTION: Keep going horizontal state to prevent leaks during remove the pressure sensor. Tightening torque: 7.8 ~ 9.8 N.m (0.8 ~ 1.0 kgf.m, 5.8 ~ 7.2 lb-ft)

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Installation is the reverse of removal.