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 for 1 s or more.

Fail-safe

•  Turn on the brake light which the malfunction is not occurring.

Possible cause

•  Electrical supply unit (ESU) connector or terminal malfunction

•  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

•  Open circuit in brake light signal circuit

•  Brake light (LH) malfunction

•  Brake light (RH) malfunction

•  High−mount brake light connector or terminal malfunction

•  Open circuit in high−mount brake light ground circuit

•  Open circuit in high−mount brake light signal circuit

•  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 for 1 s or more.
Fail-safe	• Turn on the brake light which the malfunction is not occurring.
Possible cause	• Electrical supply unit (ESU) connector or terminal malfunction • 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 • Open circuit in brake light signal circuit • Brake light (LH) malfunction • Brake light (RH) malfunction • High−mount brake light connector or terminal malfunction • Open circuit in high−mount brake light ground circuit • Open circuit in high−mount brake light signal circuit • 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.)

•  Switch the main power ON (READY off or on) and wait for 1 s or more.

•  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

DETERMINE MALFUNCTIONING LIGHT

•  Depress the brake pedal.

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

―  Brake light (LH)

―  Brake light (RH)

―  High-mount brake light

Yes

All lights do not turned on:

•  Go to the next step.

Brake light (LH) and brake light (RH) do not turned on:

•  Go to Step 4.

High-mount brake light does not turned on:

•  Go to Step 11.

No

Go to the next step.

3

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.

4

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.

5

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.

6

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.

7

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.

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 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

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

11

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.

12

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.

13

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.

14

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.

15

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.)

16

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.)

•  Switch the main power ON (READY off or on) and wait for 1 s or more.

•  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 [L.H.D. (E)].)

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.].)

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.)

•  Switch the main power ON (READY off or on) and wait for 1 s or more.

•  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 [L.H.D. (E)].)

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.].)

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.)

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.) • Switch the main power ON (READY off or on) and wait for 1 s or more. • 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	DETERMINE MALFUNCTIONING LIGHT • Depress the brake pedal. • Are there any lights among the following which are not turned on? ― Brake light (LH) ― Brake light (RH) ― High-mount brake light	Yes	All lights do not turned on: • Go to the next step. Brake light (LH) and brake light (RH) do not turned on: • Go to Step 4. High-mount brake light does not turned on: • Go to Step 11.
2		No	Go to the next step.
3	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.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	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.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	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.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	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.
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 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.)
10		No	Repair or replace the malfunctioning location and perform the repair completion verification.
11	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.
11		No	Repair or replace the malfunctioning location and perform the repair completion verification.
12	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.
12		No	Repair or replace the malfunctioning location and perform the repair completion verification.
13	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.
13		No	Repair or replace the malfunctioning location and perform the repair completion verification.
14	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.
14		No	Repair or replace the malfunctioning location and perform the repair completion verification.
15	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.
15		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See HIGH-MOUNT BRAKE LIGHT REMOVAL/INSTALLATION.)
16	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.) • Switch the main power ON (READY off or on) and wait for 1 s or more. • 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 [L.H.D. (E)].) (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.].) If the CAN communication is normal, replace the malfunctioning location and perform the repair completion verification. (See ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION.)
16		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.) • Switch the main power ON (READY off or on) and wait for 1 s or more. • 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 [L.H.D. (E)].) (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.].) 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.)
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.