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DTC 74 2-4 BRAKE TIMING SOLENOID

DTC 74 2-4 BRAKE TIMING SOLENOID

DIAGNOSIS:

The output signal circuit of 2-4 brake timing solenoid is open or shorted.

TROUBLE SYMPTOM:

Excessive shift shock.

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. 16 — (B11) No. 4:

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 of harness between TCM connector and chassis ground.

Connector & terminal

(B54) No. 16 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes


No

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


CHECK 2-4 BRAKE TIMING SOLENOID.

Measure the resistance between transmission connector terminals.

Connector & terminal

(T4) No. 4 — No. 16:

Is the resistance 10 — 16 Ω?

Yes


No


CHECK OUTPUT SIGNAL EMITTED FROM TCM.

Connect the connectors to TCM and transmission.

Turn the ignition switch to ON (engine OFF).

Move the select lever to “D” range.

Measure the voltage between TCM connector and chassis ground.

Connector & terminal

(B54) No. 15 (+) — Chassis ground (−):

Is the voltage more than 9 V?

Yes


No


CHECK OUTPUT SIGNAL EMITTED FROM TCM.

Connect the connectors to TCM and transmission.

Lift-up the vehicle and support with rigid rack.

Note

Raise all wheels off ground.


Start the engine and warm-up the transmission until ATF temperature is above 80°C (176°F).

Note

If ambient temperature is below 0°C (32°F), drive the vehicle until ATF reaches its operating temperature.


Move the selector lever to “1” range, and slowly increase vehicle speed to 10 km/h (6 MPH).

Note

The speed difference between front and rear wheels may light the ABS warning light, but this indicates no malfunction. When AT control diagnosis is finished, perform the ABS memory clearance procedure of on-board diagnostics system.


Measure the voltage between TCM connector and chassis ground.

Connector & terminal

(B54) No. 16 (+) — Chassis ground (−):

Is the voltage less than 1 V?

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 low clutch timing solenoid and transmission.


No


CHECK POOR CONTACT.

Is there poor contact in 2-4 brake timing solenoid circuit?

Yes

Repair the poor contact.


No

Replace the TCM.


CHECK 2-4 BRAKE TIMING SOLENOID (IN TRANSMISSION).

Remove the transmission connector from bracket.

Lift-up the vehicle and support with rigid rack.

Note

Raise all wheels off ground.


Drain the ATF.

Important

Do not drain the ATF until it cools down.


Remove the oil pan, and disconnect connector from 2-4 brake timing solenoid.

Measure the resistance between 2-4 brake timing solenoid connector and transmission ground.

Terminals

No. 1 — Transmission ground:

Is the resistance 10 — 16 Ω?

Yes


No

Replace the 2-4 brake timing solenoid.


CHECK HARNESS CONNECTOR BETWEEN 2-4 BRAKE TIMING SOLENOID AND TRANSMISSION.

Measure the resistance of harness between 2-4 brake timing solenoid and transmission connector.

Connector & terminal

(AT8) No. 1 — (T4) No. 4:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between 2-4 brake timing solenoid and transmission connector.


CHECK HARNESS CONNECTOR BETWEEN 2-4 BRAKE TIMING SOLENOID AND TRANSMISSION.

Measure the resistance of harness between 2-4 brake timing solenoid connector and transmission ground.

Connector & terminal

(T4) No. 4 — 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 connector in 2-4 brake timing solenoid and transmission.


No

Repair the short circuit harness between 2-4 brake timing solenoid and transmission connector.