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DTC C0023:14 [BODY CONTROL MODULE (BCM)]

id0902r7118800

Outline

System malfunction location

Brake light circuit malfunction

Detection condition

•  The electrical supply unit (ESU) detects an open circuit in the brake light circuit.

Fail-safe

Not applicable

Possible cause

•  Rear combination light (LH) connector or terminal malfunction

•  Open circuit in brake light (LH) ground circuit

•  Rear combination light (RH) connector or terminal malfunction

•  Open circuit in brake light (RH) ground circuit

•  High−mount brake light connector or terminal malfunction

•  Open circuit in high−mount brake light ground circuit

•  Electrical supply unit (ESU) connector or terminal malfunction

•  Open circuit in brake light signal circuit

•  Open circuit in high−mount brake light signal circuit

•  Brake light (LH) malfunction

•  Brake light (RH) malfunction

•  High−mount brake light malfunction

•  Electrical supply unit (ESU) malfunction

•  Body control module (BCM) malfunction

System malfunction location	Brake light circuit malfunction
Detection condition	• The electrical supply unit (ESU) detects an open circuit in the brake light circuit.
Fail-safe	Not applicable
Possible cause	• Rear combination light (LH) connector or terminal malfunction • Open circuit in brake light (LH) ground circuit • Rear combination light (RH) connector or terminal malfunction • Open circuit in brake light (RH) ground circuit • High−mount brake light connector or terminal malfunction • Open circuit in high−mount brake light ground circuit • Electrical supply unit (ESU) connector or terminal malfunction • Open circuit in brake light signal circuit • Open circuit in high−mount brake light signal circuit • Brake light (LH) malfunction • Brake light (RH) malfunction • High−mount brake light malfunction • Electrical supply unit (ESU) malfunction • Body control module (BCM) malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY BODY CONTROL MODULE (BCM) DTCs AGAIN

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the DTC inspection for the body control module (BCM).
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Go to the next step.

No

Go to repair completion verification 2.

2

INSPECT REAR COMBINATION LIGHT (LH) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

3

INSPECT BRAKE LIGHT (LH) GROUND CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

4

INSPECT REAR COMBINATION LIGHT (RH) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

5

INSPECT BRAKE LIGHT (RH) GROUND CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

6

INSPECT HIGH−MOUNT BRAKE LIGHT CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

7

INSPECT HIGH−MOUNT BRAKE LIGHT GROUND CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

8

INSPECT ELECTRICAL SUPPLY UNIT (ESU) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

9

INSPECT BRAKE LIGHT SIGNAL CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

10

INSPECT HIGH-MOUNT BRAKE LIGHT SIGNAL CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for an open circuit.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

11

INSPECT BRAKE LIGHT FOR MALFUNCTION

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Depress the brake pedal.

•  Are there any lights among the following which are not turned on?

―  Brake light (LH)

―  Brake light (RH)

Yes

If the brake light (LH) malfunction does not turn on:

•  Replace the brake light (LH) malfunction and perform the repair completion verification.
(See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)

If the brake light (RH) malfunction does not turn on:

•  Replace the brake light (RH) malfunction and perform the repair completion verification.
(See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)

No

Go to the next step.

12

INSPECT HIGH-MOUNT BRAKE LIGHT FOR MALFUNCTION

•  Inspect the applicable part.
(See HIGH-MOUNT BRAKE LIGHT INSPECTION.)

•  Is the part normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

(See HIGH-MOUNT BRAKE LIGHT REMOVAL/INSTALLATION.)

13

INSPECT ELECTRICAL SUPPLY UNIT (ESU) FOR MALFUNCTION DEPENDING ON REPEATABILITY

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the DTC inspection for the body control module (BCM).
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, replace the malfunctioning location and perform the repair completion verification.

(See ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION.)

No

Go to the next step.

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the DTC inspection for the body control module (BCM).
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, perform the diagnosis from Step 1.

•  If the malfunction recurs, replace the body control module (BCM), then go to the next step.
(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)

No

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTC IS DISPLAYED

•  Perform the DTC inspection.
(See DTC INSPECTION.)

•  Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.

Step	Inspection	Results	Action
1	VERIFY BODY CONTROL MODULE (BCM) DTCs AGAIN • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Go to the next step.
1		No	Go to repair completion verification 2.
2	INSPECT REAR COMBINATION LIGHT (LH) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification.
3	INSPECT BRAKE LIGHT (LH) GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for an open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT REAR COMBINATION LIGHT (RH) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT BRAKE LIGHT (RH) GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for an open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT HIGH−MOUNT BRAKE LIGHT CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT HIGH−MOUNT BRAKE LIGHT GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for an open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification.
8	INSPECT ELECTRICAL SUPPLY UNIT (ESU) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
8		No	Repair or replace the malfunctioning location and perform the repair completion verification.
9	INSPECT BRAKE LIGHT SIGNAL CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for an open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
9		No	Repair or replace the malfunctioning location and perform the repair completion verification.
10	INSPECT HIGH-MOUNT BRAKE LIGHT SIGNAL CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for an open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
10		No	Repair or replace the malfunctioning location and perform the repair completion verification.
11	INSPECT BRAKE LIGHT FOR MALFUNCTION • Install/connect the part removed/disconnected during the troubleshooting procedure. • Depress the brake pedal. • Are there any lights among the following which are not turned on? ― Brake light (LH) ― Brake light (RH)	Yes	If the brake light (LH) malfunction does not turn on: • Replace the brake light (LH) malfunction and perform the repair completion verification. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.) If the brake light (RH) malfunction does not turn on: • Replace the brake light (RH) malfunction and perform the repair completion verification. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
11		No	Go to the next step.
12	INSPECT HIGH-MOUNT BRAKE LIGHT FOR MALFUNCTION • Inspect the applicable part. (See HIGH-MOUNT BRAKE LIGHT INSPECTION.) • Is the part normal?	Yes	Go to the next step.
12		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See HIGH-MOUNT BRAKE LIGHT REMOVAL/INSTALLATION.)
13	INSPECT ELECTRICAL SUPPLY UNIT (ESU) FOR MALFUNCTION DEPENDING ON REPEATABILITY • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, replace the malfunctioning location and perform the repair completion verification. (See ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION.)
13		No	Go to the next step.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the body control module (BCM), then go to the next step. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTC IS DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.