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DTC B1277:14 [BODY CONTROL MODULE (BCM)]

id0902r7117500

Outline

System malfunction location

Back-up light circuit malfunction

Detection condition

•  The electrical supply unit (ESU) detects an open circuit or short to ground in the back-up light circuit.

Fail-safe

Not applicable

Possible cause

•  Liftgate light (LH) connector or terminal malfunction

•  Liftgate light (RH) connector or terminal malfunction

•  Open circuit in back-up light ground circuit

•  Electrical supply unit (ESU) connector or terminal malfunction

•  Short to ground in back-up light signal circuit

•  Open circuit in back-up light signal circuit

•  Back-up light (LH) malfunction

•  Back-up light (RH) malfunction

•  Electrical supply unit (ESU) malfunction

•  Body control module (BCM) malfunction

System malfunction location	Back-up light circuit malfunction
Detection condition	• The electrical supply unit (ESU) detects an open circuit or short to ground in the back-up light circuit.
Fail-safe	Not applicable
Possible cause	• Liftgate light (LH) connector or terminal malfunction • Liftgate light (RH) connector or terminal malfunction • Open circuit in back-up light ground circuit • Electrical supply unit (ESU) connector or terminal malfunction • Short to ground in back-up light signal circuit • Open circuit in back-up light signal circuit • Back-up light (LH) malfunction • Back-up light (RH) 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 LIFTGATE 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 LIFTGATE 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.

4

INSPECT BACK-UP 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.

5

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.

6

INSPECT BACK-UP LIGHT SIGNAL CIRCUIT FOR SHORT TO GROUND

•  Inspect the applicable circuit for a short to ground.
(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.

7

INSPECT BACK-UP 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.

8

INSPECT BACK-UP LIGHT FOR MALFUNCTION

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

•  Perform the following operation.

―  Shift the selector lever to the R position. (ATX)

―  Shift the shift lever to the reverse position. (MTX)

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

―  Back-up light (LH) (liftgate light (LH))

―  Back-up light (RH) (liftgate light (RH))

Yes

If the back-up light (LH) (liftgate light (LH)) does not turn on:

•  Replace the liftgate light (LH) and perform the repair completion verification.
(See LIFTGATE LIGHT REMOVAL/INSTALLATION.)

If the back-up light (RH) (liftgate light (RH)) does not turn on:

•  Replace the liftgate light (RH) and perform the repair completion verification.
(See LIFTGATE LIGHT REMOVAL/INSTALLATION.)

No

Go to the next step.

9

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 repair completion verification 2.

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 LIFTGATE 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 LIFTGATE 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.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT BACK-UP 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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	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.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT BACK-UP LIGHT SIGNAL CIRCUIT FOR SHORT TO GROUND • Inspect the applicable circuit for a short to ground. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT BACK-UP 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.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification.
8	INSPECT BACK-UP LIGHT FOR MALFUNCTION • Install/connect the part removed/disconnected during the troubleshooting procedure. • Perform the following operation. ― Shift the selector lever to the R position. (ATX) ― Shift the shift lever to the reverse position. (MTX) • Are there any lights among the following which are not turned on? ― Back-up light (LH) (liftgate light (LH)) ― Back-up light (RH) (liftgate light (RH))	Yes	If the back-up light (LH) (liftgate light (LH)) does not turn on: • Replace the liftgate light (LH) and perform the repair completion verification. (See LIFTGATE LIGHT REMOVAL/INSTALLATION.) If the back-up light (RH) (liftgate light (RH)) does not turn on: • Replace the liftgate light (RH) and perform the repair completion verification. (See LIFTGATE LIGHT REMOVAL/INSTALLATION.)
8		No	Go to the next step.
9	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.)
9		No	Go to repair completion verification 2.
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.