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DTC P0719 TORQUE CONVERTER/BRAKE SWITCH “B” CIRCUIT LOW

DTC P0719 TORQUE CONVERTER/BRAKE SWITCH “B” CIRCUIT LOW

DIAGNOSIS:

Brake switch malfunction or input signal open circuit.

TROUBLE SYMPTOM:

Gear is not shifted down when climbing hill.

WIRING DIAGRAM:


CHECK OPERATION OF BRAKE LIGHT.

Depress the brake pedal.

Does the brake light illuminate?

Yes


No

Check the brake light circuit.


CHECK TCM INPUT SIGNAL.

Depress the brake pedal.

Measure the voltage of harness between TCM and stop light switch.

Connector & terminal

(B55) No. 20 (+) — Chassis ground (−):

Is the voltage more than 10 V?

Yes


No


HECK HARNESS CONNECTOR BETWEEN TCM BRAKE LIGHT SWITCH.

Turn the ignition switch to OFF.

Disconnect the connector from TCM and stop light switch.

Measure the resistance between TCM and stop light switch.

Connector & terminal

(B55) No. 20 — (B65) No. 3:

Is the resistance less than 1 Ω?

Yes


No

Repair the open harness between TCM and stop light switch.


CHECK HARNESS CONNECTOR BETWEEN TCM BRAKE LIGHT SWITCH.

Measure the resistance between TCM and stop light switch.

Connector & terminal

(B55) No. 20 — (B65) No. 3:

Is the resistance more than 1 MΩ?

Yes


No

Repair the short harness between TCM and stop light switch.


INSPECT POOR CONTACT.

Is there poor contact in the brake switch input signal circuit?

Yes

Repair poor contact.


No

Replace the TCM.