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DTC 79 TRANSFER DUTY SOLENOID

DTC 79 TRANSFER DUTY SOLENOID

DIAGNOSIS:

The output signal circuit of transfer duty solenoid is open or shorted.

TROUBLE SYMPTOM:


• Tight corner braking phenomenon is occurred.

• Front or rear wheels slip on the slippery road.


WIRING DIAGRAM:


CHECK HARNESS CONNECTOR BETWEEN TCM AND TRANSMISSION.

Turn the ignition switch to OFF.

Disconnect the connector from TCM and transmission.

Measure the resistance of harness between TCM and transmission connector.

Connector & terminal

(B54) No. 6 — (B11) No. 6:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between TCM and transmission connector.


CHECK HARNESS CONNECTOR BETWEEN TCM AND TRANSMISSION.

Measure the resistance harness connector between TCM and chassis ground.

Connector & terminal

(B54) No. 6 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes


No

Repair the short circuit in harness between TCM and transmission connector.


CHECK TRANSFER DUTY SOLENOID.

Measure the resistance between transmission connector and transmission terminals.

Connector & terminal

(T4) No. 6 — No. 16:

Is the resistance 10 — 17 Ω?

Yes


No


CHECK OUTPUT SIGNAL EMITTED FROM TCM USING Vehicle Diagnostic Interface.

Connect the connectors to TCM and transmission.

Connect the Vehicle Diagnostic Interface to data link connector.

Turn the ignition switch to ON (engine OFF) and turn Vehicle Diagnostic Interface switch to ON.

Move the select lever to “D” range with throttle fully open (vehicle speed 0 km/h or 0 MPH).

Read the data of transfer duty solenoid using Vehicle Diagnostic Interface.


• Transfer duty solenoid is indicated in “%”.


Is the value 80 — 95%?

Yes


No


CHECK OUTPUT SIGNAL EMITTED FROM TCM USING Vehicle Diagnostic Interface.

Move the select lever to “N” range with throttle fully close (vehicle speed 0 km/h or 0 MPH).

Read the data of transfer duty solenoid using Vehicle Diagnostic Interface.


• Transfer duty solenoid is indicated in “%”.


Is the value approx. 40%?

Yes

Even if the AT OIL TEMP warning light blinks, the circuit has returned to a normal condition at this time. A temporary poor contact of the connector or harness may be the cause. Repair the harness or connector in transfer duty solenoid and TCM connector.


No


CHECK POOR CONTACT.

Is there poor contact in transfer duty solenoid circuit?

Yes

Repair the poor contact.


No

Replace the TCM.


CHECK TRANSFER DUTY SOLENOID (IN TRANSMISSION).

Lift-up the vehicle and support with rigid racks.

Note

Raise all wheels off ground.


Drain the ATF.

Important

Do not drain the ATF until it cools down.


Remove the extension case and disconnect connector from transfer duty solenoid.

Measure the resistance between transfer duty solenoid connector and transmission ground.

Connector & terminal

(AT4) No. 1 — Transmission ground:

Is the resistance 10 — 17 Ω?

Yes


No

Replace the transfer duty solenoid.


CHECK HARNESS CONNECTOR BETWEEN TRANSFER DUTY SOLENOID AND TRANSMISSION.

Measure the resistance of harness between transfer duty solenoid and transmission connector.

Connector & terminal

(T4) No. 6 — (AT4) No. 1:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between transfer duty solenoid and transmission connector.


CHECK HARNESS CONNECTOR BETWEEN TRANSFER DUTY SOLENOID AND TRANSMISSION.

Measure the resistance of harness between transmission connector and transmission ground.

Connector & terminal

(T4) No. 6 — Transmission ground:

Is the resistance more than 1 MΩ?

Yes

Even if the AT OIL TEMP warning light blinks, the circuit has returned to a normal condition at this time. A temporary poor contact of the connector or harness may be the cause. Repair the harness or poor contact in transfer duty solenoid and transmission.


No

Repair the short circuit in harness between transfer duty solenoid and transmission connector.