DTC C0023:62/C0040:64 [DSC HU/CM]

id040262906400

Without Smart City Brake Support (SCBS)

DTC

C0040:64

Brake switch

DETECTION CONDITION

•  Accelerator pedal is depressed and brake switch on condition continues for 30 to 60 s while vehicle is driven at 10.8 km/h {6.71 mph} or more.

•  A brake switch ON signal is not input when the brake fluid pressure sensor signal reaches the specified value.

FAIL-SAFE FUNCTION

•  Refer to “Fail-safe function table”. (See DTC TABLE [DSC HU/CM].)

POSSIBLE CAUSE

•  Brake switch malfunction

•  Poor connection at each connector

•  DSC HU/CM malfunction

SYSTEM WIRING DIAGRAM

—

Diagnostic Procedure

Step	Inspection		Action
1	INSPECT BRAKE SWITCH • Inspect the brake switch. (See BRAKE SWITCH INSPECTION.) • Is the brake switch normal?	Yes	Go to the next step.
1		No	Replace the brake switch, then go to the next step. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
2	VERIFY DTC TROUBLESHOOTING COMPLETED • Using the M-MDS, clear the DTC from the DSC HU/CM. (See CLEARING DTC [DSC HU/CM].) • Using the M-MDS, perform the DSC HU/CM DTC inspection. (See DTC INSPECTION [DSC HU/CM].) • Is the same Pending DTC present?	Yes	If the malfunction recurs, replace the DSC HU/CM, then go to the next step. (See DSC HU/CM REMOVAL/INSTALLATION [L.H.D.].) (See DSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)
2		No	Go to the next step.
3	VERIFY NO DTC IS PRESENT • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [DSC HU/CM].)
3	VERIFY NO DTC IS PRESENT • Are any DTCs present?	No	DTC troubleshooting completed.

With Smart City Brake Support (SCBS)

DTC

C0023:62

Brake switch

C0040:64

DETECTION CONDITION

•  C0023:62

―  Brake light signal cannot be detected even though brake light signal is requested.

―  Error detected in signal from body control module (BCM) via CAN communication.

―  The brake light signal that the DSC HU/CM received via hard wire does not correspond with the brake light signal it received via CAN communication from the body control module (BCM) for a continuous 5 s.

―  The brake fluid pressure is the specification or more for a continuous 2 s even though the brake light signal that the DSC HU/CM received via hard wire is OFF.

•  C0040:64

―  Accelerator pedal is depressed and brake switch on condition continues for 30 to 60 s while vehicle is driven at 10.8 km/h {6.71 mph} or more.

―  A brake switch ON signal is not input when the brake fluid pressure sensor signal reaches the specified value.

FAIL-SAFE FUNCTION

•  Refer to “Fail-safe function table”. (See DTC TABLE [DSC HU/CM].)

POSSIBLE CAUSE

•  Brake switch malfunction

•  Open or short circuit in wiring harness between brake switch terminal D and brake light relay terminal B

•  Brake light relay malfunction

•  Open or short circuit in wiring harness between brake light relay terminal D and DSC HU/CM terminal O

•  Body control module (BCM) malfunction

•  Poor connection at each connector

•  DSC HU/CM malfunction

Diagnostic Procedure

Step	Inspection		Action
1	INSPECT BRAKE LIGHT RELAY VOLTAGE • Remove the brake light relay. (See RELAY LOCATION.) • Measure the voltage between brake light relay terminal B (wiring harness-side) and body ground. • Is the voltage within followings? ― Brake pedal depressed: B+ ― Brake pedal released: 1.0 V or less	Yes	Go to Step 4.
1		No	• If it is B+ under any condition, then go to the next step. • If it is 1.0 V or less under any condition, then go to Step 3.
2	INSPECT BRAKE SWITCH • Inspect brake switch. (See BRAKE SWITCH INSPECTION.) • Is the brake switch normal?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between brake switch terminal D and brake light relay terminal B. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to power circuit. Go to Step 7.
2		No	Replace the brake switch, then go to Step 7. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
3	INSPECT BRAKE SWITCH • Inspect brake switch. (See BRAKE SWITCH INSPECTION.) • Is the brake switch normal?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between brake switch terminal D and brake light relay terminal B. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open or short to ground circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open or short to ground circuit. Go to Step 7.
3		No	Replace the brake switch, then go to Step 7. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D.].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
4	INSPECT BRAKE LIGHT RELAY • Remove the brake light relay. (See RELAY LOCATION.) • Inspect brake light relay. (See RELAY INSPECTION.) • Is the brake light relay normal?	Yes	Go to the next step.
4		No	Replace the brake light relay, then go to Step 7.
5	INSPECT WIRING HARNESS BETWEEN BRAKE LIGHT RELAY AND DSC HU/CM FOR OPEN OR SHORT CIRCUIT • Disconnect the DSC HU/CM connector. • Measure the voltage between DSC HU/CM terminal O (wiring harness-side) and body ground. • Is the voltage within followings? ― Brake pedal depressed: B+ ― Brake pedal released: 1.0 V or less	Yes	Go to the next step.
5		No	• If it is B+ under any condition, refer to the wiring diagram and verify whether or not there is a common connector between brake light relay terminal D and DSC HU/CM terminal O. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to power circuit. • If it is 1.0 V or less under any condition, refer to the wiring diagram and verify whether or not there is a common connector between brake light relay terminal D and DSC HU/CM terminal O. If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open or short to ground circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open or short to ground circuit. • Go to Step 7.
6	VERIFY BODY CONTROL MODULE (BCM) DTC • Using the M-MDS, perform the body control module (BCM) DTC inspection. (See DTC INSPECTION [BCM].) • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [BCM].) DTC troubleshooting completed, then go to the next step.
6		No	Go to the next step.
7	VERIFY DTC TROUBLESHOOTING COMPLETED • Using the M-MDS, clear the DTC from the DSC HU/CM. (See CLEARING DTC [DSC HU/CM].) • Using the M-MDS, perform the DSC HU/CM DTC inspection. (See DTC INSPECTION [DSC HU/CM].) • Is the same Pending DTC present?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the DSC HU/CM, then go to the next step. (See DSC HU/CM REMOVAL/INSTALLATION [L.H.D.].) (See DSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)
7		No	Go to the next step.
8	VERIFY NO DTC IS PRESENT • Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [DSC HU/CM].)
8	VERIFY NO DTC IS PRESENT • Are any DTCs present?	No	DTC troubleshooting completed.

DTC	C0040:64	Brake switch
DETECTION CONDITION		• Accelerator pedal is depressed and brake switch on condition continues for 30 to 60 s while vehicle is driven at 10.8 km/h {6.71 mph} or more. • A brake switch ON signal is not input when the brake fluid pressure sensor signal reaches the specified value.
FAIL-SAFE FUNCTION		• Refer to “Fail-safe function table”. (See DTC TABLE [DSC HU/CM].)
POSSIBLE CAUSE		• Brake switch malfunction • Poor connection at each connector • DSC HU/CM malfunction
SYSTEM WIRING DIAGRAM		—

DTC	C0023:62	Brake switch
	C0040:64
DETECTION CONDITION		• C0023:62 ― Brake light signal cannot be detected even though brake light signal is requested. ― Error detected in signal from body control module (BCM) via CAN communication. ― The brake light signal that the DSC HU/CM received via hard wire does not correspond with the brake light signal it received via CAN communication from the body control module (BCM) for a continuous 5 s. ― The brake fluid pressure is the specification or more for a continuous 2 s even though the brake light signal that the DSC HU/CM received via hard wire is OFF. • C0040:64 ― Accelerator pedal is depressed and brake switch on condition continues for 30 to 60 s while vehicle is driven at 10.8 km/h {6.71 mph} or more. ― A brake switch ON signal is not input when the brake fluid pressure sensor signal reaches the specified value.
FAIL-SAFE FUNCTION		• Refer to “Fail-safe function table”. (See DTC TABLE [DSC HU/CM].)
POSSIBLE CAUSE		• Brake switch malfunction • Open or short circuit in wiring harness between brake switch terminal D and brake light relay terminal B • Brake light relay malfunction • Open or short circuit in wiring harness between brake light relay terminal D and DSC HU/CM terminal O • Body control module (BCM) malfunction • Poor connection at each connector • DSC HU/CM malfunction