Inspection Procedure
- CHECK OPEN/SHORT IN CIRCUIT OF BRAKE SWITCH
- Disconnect the connector from the HECU, and measure the voltage between terminal 21 of the HECU connector and the body ground, not pushing the brake pedal.
Specification: Battery (B+)
- Disconnect the connector from the HECU, and measure the voltage between terminal 21 of the HECU connector and the body ground, pushing the brake pedal.
Specification: 0V
Is the voltage within the specification?
NO
- Repair harness and connector of the brake switch.
YES
- Check open/short in circuit of brake lamp switch
- Disconnect the connector from the HECU, and measure the voltage between terminal 21 of the HECU connector and the body ground, not pushing the brake pedal.
- CHECK OPEN/SHORT IN CIRCUIT OF BRAKE LAMP SWITCH
- Disconnect the connector from the HECU, and measure the voltage between terminal 5 of the HECU connector and the body ground, not pushing the brake pedal.
Specification: 0V
- Disconnect the connector from the HECU, and measure the voltage between terminal 21 of the HECU connector and the body ground, pushing the brake pedal.
Specification: Battery (B+)
Is the voltage within the specification?
NO
- Repair harness and connector of the brake lamp switch.
YES
- After clearing the DTC and driving the vehicle at 40Km/h speed or more, if the ESC lamp is ON and the same DTC shows again, replace the HECU and recheck.
- Disconnect the connector from the HECU, and measure the voltage between terminal 5 of the HECU connector and the body ground, not pushing the brake pedal.