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DTC B13BD:87 [DASH-ELECTRICAL SUPPLY UNIT]

id0702k8004400

Outline

System malfunction location

Communication error with heated steering wheel control unit

Detection condition

•  The dash-electrical supply unit cannot receive LIN signal from the heated steering wheel control unit.

Fail-safe

•  Stops the steering warmer output.

Possible cause

•  Clock Spring connector or terminal malfunction

•  Heated steering wheel control unit connector or terminal malfunction

•  Clock spring malfunction

•  Dash-electrical supply unit connector or terminals malfunction

•  Short to ground in heated steering wheel control unit LIN communication line

•  Short to power supply in heated steering wheel control unit LIN communication line

•  Open circuit in heated steering wheel control unit LIN communication line

•  Heated steering wheel control unit malfunction

•  Dash-electrical supply unit malfunction

System malfunction location	Communication error with heated steering wheel control unit
Detection condition	• The dash-electrical supply unit cannot receive LIN signal from the heated steering wheel control unit.
Fail-safe	• Stops the steering warmer output.
Possible cause	• Clock Spring connector or terminal malfunction • Heated steering wheel control unit connector or terminal malfunction • Clock spring malfunction • Dash-electrical supply unit connector or terminals malfunction • Short to ground in heated steering wheel control unit LIN communication line • Short to power supply in heated steering wheel control unit LIN communication line • Open circuit in heated steering wheel control unit LIN communication line • Heated steering wheel control unit malfunction • Dash-electrical supply unit malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

INSPECT CLOCK SPRING 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.

2

INSPECT HEATED STEERING WHEEL 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 CLOCK SPRING FOR MALFUNCTION

•  Inspect the applicable part.
(See CLOCK SPRING INSPECTION [STANDARD DEPLOYMENT CONTROL SYSTEM].)

(See CLOCK SPRING INSPECTION [TWO-STEP DEPLOYMENT CONTROL SYSTEM].)

•  Is the part normal?

Yes

Go to the next step.

No

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

(See CLOCK SPRING REMOVAL/INSTALLATION [STANDARD DEPLOYMENT CONTROL SYSTEM].)

(See CLOCK SPRING REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM].)

4

INSPECT DASH-ELECTRICAL SUPPLY UNIT CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

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

No

Go to the next step.

5

INSPECT HEATED STEERING WHEEL CONTROL UNIT LIN COMMUNICATION LINE 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.

6

INSPECT HEATED STEERING WHEEL CONTROL UNIT LIN COMMUNICATION LINE FOR SHORT TO POWER SUPPLY

•  Inspect the applicable circuit for a short to power supply.
(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 HEATED STEERING WHEEL CONTROL UNIT LIN COMMUNICATION LINE 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 HEATED STEERING WHEEL CONTROL UNIT 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 dash-electrical supply unit.
(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 HEATED STEERING WHEEL CONTROL UNIT 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 dash-electrical supply unit.
(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 dash-electrical supply unit, then go to the next step.
(See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].)

(See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)

No

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTCs DISPLAYED

•  Perform the DTC inspection.
(See DTC INSPECTION.)

•  Are any DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.

Step	Inspection	Results	Action
1	INSPECT CLOCK SPRING CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
1		No	Repair or replace the malfunctioning location and perform the repair completion verification.
2	INSPECT HEATED STEERING WHEEL 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 CLOCK SPRING FOR MALFUNCTION • Inspect the applicable part. (See CLOCK SPRING INSPECTION [STANDARD DEPLOYMENT CONTROL SYSTEM].) (See CLOCK SPRING INSPECTION [TWO-STEP DEPLOYMENT CONTROL SYSTEM].) • Is the part normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See CLOCK SPRING REMOVAL/INSTALLATION [STANDARD DEPLOYMENT CONTROL SYSTEM].) (See CLOCK SPRING REMOVAL/INSTALLATION [TWO-STEP DEPLOYMENT CONTROL SYSTEM].)
4	INSPECT DASH-ELECTRICAL SUPPLY UNIT CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
4		No	Go to the next step.
5	INSPECT HEATED STEERING WHEEL CONTROL UNIT LIN COMMUNICATION LINE 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.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT HEATED STEERING WHEEL CONTROL UNIT LIN COMMUNICATION LINE FOR SHORT TO POWER SUPPLY • Inspect the applicable circuit for a short to power supply. (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 HEATED STEERING WHEEL CONTROL UNIT LIN COMMUNICATION LINE 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 HEATED STEERING WHEEL CONTROL UNIT 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 dash-electrical supply unit. (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 HEATED STEERING WHEEL CONTROL UNIT REMOVAL/INSTALLATION.)
8		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 dash-electrical supply unit. (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 dash-electrical supply unit, then go to the next step. (See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].) (See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.