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DTC U2640:14 [BODY CONTROL MODULE (BCM)]

id0902r7109000

Outline

System malfunction location

LF control unit power supply circuit (B1+) malfunction

Detection condition

•  The LF control unit detects an open circuit or short to ground in the power supply circuit (B1+).

Fail-safe

Not applicable

Possible cause

•  LF control unit connector or terminal malfunction

•  Short to ground or open circuit in LF control unit power supply circuit (B1+)

•  LF control unit malfunction

•  Body control module (BCM) malfunction

System malfunction location	LF control unit power supply circuit (B1+) malfunction
Detection condition	• The LF control unit detects an open circuit or short to ground in the power supply circuit (B1+).
Fail-safe	Not applicable
Possible cause	• LF control unit connector or terminal malfunction • Short to ground or open circuit in LF control unit power supply circuit (B1+) • LF control unit 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 LF CONTROL UNIT 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 LF CONTROL UNIT POWER SUPPLY CIRCUIT (B1+) FOR SHORT TO GROUND AND OPEN CIRCUIT

•  Inspect the applicable circuit for a short to ground and 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 LF CONTROL UNIT FOR MALFUNCTION

•  Inspect the applicable part.
(See LF CONTROL UNIT INSPECTION [(E)].)

•  Is the part normal?

Yes

Go to the next step.

No

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

(See LF CONTROL UNIT REMOVAL/INSTALLATION [(E)].)

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 LF CONTROL UNIT 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 LF CONTROL UNIT POWER SUPPLY CIRCUIT (B1+) FOR SHORT TO GROUND AND OPEN CIRCUIT • Inspect the applicable circuit for a short to ground and 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 LF CONTROL UNIT FOR MALFUNCTION • Inspect the applicable part. (See LF CONTROL UNIT INSPECTION [(E)].) • Is the part normal?	Yes	Go to the next step.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See LF CONTROL UNIT REMOVAL/INSTALLATION [(E)].)
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.