AUTOMATIC TRANSMISSION (DIAGNOSTICS)(4AT)(D) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC P0724 BRAKE SWITCH CIRCUIT HIGH

DTC DETECTING CONDITION:

Stop light switch malfunction, open input signal circuit

TROUBLE SYMPTOM:

Gear is not shifted down when climbing a hill.

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK INPUT SIGNAL FROM TCM.

1) Disconnect the harness connector of TCM.

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

Connector & terminal

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

Is the voltage 10 V or more?

2.CHECK STOP LIGHT SWITCH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from stop light switch.

3) Measure the resistance of harness between stop light switch connectors.

Connector & terminal

Models with cruise control

No. 2 — No. 3:

Models without cruise control

No. 1 — No. 2:

Is the resistance 1 MΩ or more?

Replace the stop light switch.

3.CHECK HARNESS CONNECTOR BETWEEN TCM AND STOP LIGHT SWITCH.

1) Turn the ignition switch to ON.

2) Measure the voltage of harness between TCM and chassis ground.

Connector & terminal

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

Is the voltage less than 1 V?

Repair the short circuit of harness between TCM and stop light switch.

4.CHECK POOR CONTACT.

Is there poor contact in input signal circuit of the stop light switch?

Repair the poor contact.

Replace the TCM.