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DTC P0724 TORQUE CONVERTER/BRAKE SWITCH “B” CIRCUIT HIGH

DTC P0724 TORQUE CONVERTER/BRAKE SWITCH “B” CIRCUIT HIGH

DIAGNOSIS:

Brake switch malfunction or open brake switch input signal circuit.

TROUBLE SYMPTOM:

Gear is not shifted down when climbing hill.

WIRING DIAGRAM:


CHECK TCM INPUT SIGNAL.

Disconnect the harness connector from TCM.

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


CHECK STOP LIGHT SWITCH.

Turn the ignition switch OFF.

Disconnect the connector from stop light switch.

Measure the resistance between stop light switch connector.

Connector & terminal

No. 2 — No. 3:

Is the resistance more than 1 MΩ?

Yes


No

Replace the stop light switch.


CHECK HARNESS CONNECTOR BETWEEN TCM AND STOP LIGHT SWITCH.

Turn the ignition switch ON.

Measure the voltage between TCM and chassis ground.

Connector & terminal

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

Is the voltage less than 1 V?

Yes


No

Repair the short in power supply circuit to 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.