P0703

DTC P0703 - BRAKE SWITCH INPUT MALFUNCTION

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic Trouble Codes.




WIRING DIAGRAM

10AY1: CHECK OPERATION OF BRAKE LIGHT

CHECK: Does brake light come on when depressing the brake pedal?

YES: Go to step 10AY2.

NO: Repair or replace brake light circuit.

10AY2: CHECK HARNESS BETWEEN TCM AND BRAKE LIGHT SWITCH CONNECTOR.
1. Disconnect connectors from TCM and brake light switch.

Connector & terminal (B55) No.24 - (B64) No.2: (B55) No.24 - (B65) No.3 (With cruise control):

2. Measure resistance of harness between TCM and brake light switch connector.

CHECK: Is the resistance less than 1 ohm?

YES: Go to step 10AY3.

NO: Repair or replace harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between TOM and brake light switch connector
- Poor contact in TCM connector
- Poor contact in brake light switch connector

10AY3: CHECK HARNESS BETWEEN TCM AND BRAKE LIGHT SWITCH CONNECTOR.

Connector & terminal (B55) No.24 - Chassis ground:

Measure resistance of harness between TCM and chassis ground.

CHECK: Is the resistance more than 1 M.Ohm?

YES: Go to step 10AY4.

NO: Repair ground short circuit in harness between TCM and brake light switch connector.

10AY4: CHECK INPUT SIGNAL FOR TCM.
1. Connect connectors to TCM and brake light switch.

Connector & terminal (B55) No.24 (+) - Chassis ground (-):

2. Measure voltage between TCM and chassis ground.

CHECK: Is the voltage less than 1 Volt when releasing the brake pedal?

YES: Go to step 10AY5.

NO: Adjust or replace brake light switch.

10AY5: CHECK INPUT SIGNAL FOR TCM.

Connector & terminal (B55) No.24 (+) - Chassis ground (-):

Measure voltage between TCM and chassis ground.

CHECK: Is the voltage more than 10 V when depressing the brake pedal?

YES: Go to step 10AY6.

NO: Adjust or replace brake light switch.

10AY6: CHECK POOR CONTACT.
Check poor contact in TCM connector.

CHECK: Is there poor contact in TCM connector?

YES: Repair poor contact in TCM connector.

NO: Replace TCM.