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DTC C1A56:87 [BODY CONTROL MODULE (BCM)]

id0902r7116500

Outline

System malfunction location

Communication error with wheel unit (LF)

Detection condition

•  The body control module (BCM) cannot receive the signals from the wheel unit (LF).

Fail-safe

Not applicable

Possible cause

•  Mis-installation of wheel unit (LF)

•  Wheel unit malfunction (LF)

•  Body control module (BCM) malfunction

System wiring diagram

Not applicable

Connector diagram

Not applicable

System malfunction location	Communication error with wheel unit (LF)
Detection condition	• The body control module (BCM) cannot receive the signals from the wheel unit (LF).
Fail-safe	Not applicable
Possible cause	• Mis-installation of wheel unit (LF) • Wheel unit malfunction (LF) • Body control module (BCM) malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable

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

VERIFY WHEEL UNIT (LF) IS INSTALLED TO WHEEL (LF)

•  Visually inspect the wheel unit (LF).

•  Is a wheel (LF) installed with a wheel unit (LF)?

Yes

Go to the next step.

No

Install and register the wheel unit (LF), and perform the repair completion verification procedure.

(See WHEEL UNIT REMOVAL/INSTALLATION [(E)].)

(See WHEEL UNIT ID REGISTRATION.)

3

INSPECT WHEEL UNIT (LF) 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 and register the malfunctioning wheel unit and perform the repair completion verification.

(See WHEEL UNIT REMOVAL/INSTALLATION [(E)].)

(See WHEEL UNIT ID REGISTRATION.)

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	VERIFY WHEEL UNIT (LF) IS INSTALLED TO WHEEL (LF) • Visually inspect the wheel unit (LF). • Is a wheel (LF) installed with a wheel unit (LF)?	Yes	Go to the next step.
2		No	Install and register the wheel unit (LF), and perform the repair completion verification procedure. (See WHEEL UNIT REMOVAL/INSTALLATION [(E)].) (See WHEEL UNIT ID REGISTRATION.)
3	INSPECT WHEEL UNIT (LF) 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 and register the malfunctioning wheel unit and perform the repair completion verification. (See WHEEL UNIT REMOVAL/INSTALLATION [(E)].) (See WHEEL UNIT ID REGISTRATION.)
3		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.