Home

Mazdamanuals.com

DTC B1A79:14 [BODY CONTROL MODULE (BCM)]

id0902r7130500

Except chinese specs.

L.H.D.

Outline

System malfunction location	Rear fog light circuit malfunction
Detection condition	• The electrical supply unit (ESU) detects a short to ground in the rear fog light circuit.
Fail-safe	Not applicable
Possible cause	• Liftgate light (LH) connector or terminal malfunction • Electrical supply unit (ESU) connector or terminal malfunction • Short to ground in rear fog light signal circuit • Rear fog 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.
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 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 FOG 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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT REAR FOG LIGHT FOR MALFUNCTION • Install/connect the part removed/disconnected during the troubleshooting procedure. • Operate the fog light switch to the R.FOG position. • Does the rear fog light turn on?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification. (See LIFTGATE LIGHT REMOVAL/INSTALLATION.)
5		No	Go to the next step.
6	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.)
6		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.

R.H.D.

Outline

System malfunction location	Rear fog light circuit malfunction
Detection condition	• The electrical supply unit (ESU) detects a short to ground in the rear fog light circuit.
Fail-safe	Not applicable
Possible cause	• Liftgate light (RH) connector or terminal malfunction • Electrical supply unit (ESU) connector or terminal malfunction • Short to ground in rear fog light signal circuit • Rear fog 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.
1		No	Go to repair completion verification 2.
2	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.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification.
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 FOG 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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT REAR FOG LIGHT FOR MALFUNCTION • Install/connect the part removed/disconnected during the troubleshooting procedure. • Operate the fog light switch to the R.FOG position. • Does the rear fog light turn on?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification. (See LIFTGATE LIGHT REMOVAL/INSTALLATION.)
5		No	Go to the next step.
6	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.)
6		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.

Chinese specs.

Outline

System malfunction location

Rear fog light circuit malfunction

Detection condition

•  The electrical supply unit (ESU) detects a short to ground in the rear fog light circuit.

Fail-safe

Not applicable

Possible cause

•  Rear fog light connector or terminal malfunction

•  Electrical supply unit (ESU) connector or terminal malfunction

•  Short to ground in rear fog light signal circuit

•  Rear fog light malfunction

•  Electrical supply unit (ESU) malfunction

•  Body control module (BCM) malfunction

System malfunction location	Rear fog light circuit malfunction
Detection condition	• The electrical supply unit (ESU) detects a short to ground in the rear fog light circuit.
Fail-safe	Not applicable
Possible cause	• Rear fog light connector or terminal malfunction • Electrical supply unit (ESU) connector or terminal malfunction • Short to ground in rear fog light signal circuit • Rear fog 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 FOG 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.

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 FOG 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.

5

INSPECT REAR FOG LIGHT FOR MALFUNCTION

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

•  Operate the fog light switch to the R.FOG position.

•  Does the rear fog light turn on?

Yes

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

(See REAR FOG LIGHT REMOVAL/INSTALLATION.)

No

Go to the next step.

6

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.