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DTC B1B42:49 [VEHICLE CONTROL MODULE]

id1502c5051300

Outline

System malfunction location

Front ultrasonic sensor (LH) signal circuit malfunction

Detection condition

•  The vehicle control module (VCM) detects that the parking assist unit (ultrasonic) determined that there is a malfunction in the front ultrasonic sensor (LH) signal circuit for 11 s.

Fail-safe

(See DTC TABLE [VEHICLE CONTROL MODULE (E)].)

Possible cause

•  Front bumper malfunction

•  Front ultrasonic sensor (LH) connector or terminal malfunction

•  Parking assist unit (ultrasonic) connector or terminal malfunction

•  Short to ground in front ultrasonic sensor (LH) signal circuit

•  Short to power supply in front ultrasonic sensor (LH) signal circuit

•  Open circuit in front ultrasonic sensor (LH) signal circuit

•  Front ultrasonic sensor (LH) malfunction

•  Parking assist unit (ultrasonic) malfunction

System malfunction location	Front ultrasonic sensor (LH) signal circuit malfunction
Detection condition	• The vehicle control module (VCM) detects that the parking assist unit (ultrasonic) determined that there is a malfunction in the front ultrasonic sensor (LH) signal circuit for 11 s.
Fail-safe	(See DTC TABLE [VEHICLE CONTROL MODULE (E)].)
Possible cause	• Front bumper malfunction • Front ultrasonic sensor (LH) connector or terminal malfunction • Parking assist unit (ultrasonic) connector or terminal malfunction • Short to ground in front ultrasonic sensor (LH) signal circuit • Short to power supply in front ultrasonic sensor (LH) signal circuit • Open circuit in front ultrasonic sensor (LH) signal circuit • Front ultrasonic sensor (LH) malfunction • Parking assist unit (ultrasonic) malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

INSPECT VEHICLE CONTROL MODULE (VCM) AND BODY CONTROL MODULE (BCM) FOR MALFUNCTION

•  Perform the DTC inspection for the vehicle control module (VCM) and the body control module (BCM).
(See DTC INSPECTION.)

•  Is any of the following DTCs displayed?

―  DTC related to vehicle control module (VCM) and body control module (BCM) internal malfunction

―  DTC related to parking assist unit (ultrasonic) internal malfunction

―  DTC related to parking assist unit (ultrasonic) power supply malfunction (B14F4:16, B14F4:17)

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [VEHICLE CONTROL MODULE (E)].)

(See DTC TABLE [BODY CONTROL MODULE (BCM) (E)].)

No

Go to the next step.

2

INSPECT PARKING ASSIST UNIT (ULTRASONIC) FOR MALFUNCTION

•  Perform the DTC inspection for the parking assist unit (ultrasonic).
(See DTC INSPECTION.)

•  Is a DTC displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [PARKING ASSIST UNIT (ULTRASONIC) (E)].)

No

Go to the next step.

3

VERIFY FRONT BUMPER EXTERNAL APPEARANCE AND INSTALLATION CONDITION

•  Verify the external appearance and installation condition of the applicable part.
(See FRONT BUMPER REMOVAL/INSTALLATION [(E)].)

•  Are the external appearance and the installation condition normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location, or install the applicable part correctly and perform the repair completion verification.

(See FRONT BUMPER REMOVAL/INSTALLATION [(E)].)

4

INSPECT FRONT ULTRASONIC SENSOR (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.

5

INSPECT PARKING ASSIST UNIT (ULTRASONIC) 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 FRONT ULTRASONIC SENSOR (LH) 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 FRONT ULTRASONIC SENSOR (LH) SIGNAL CIRCUIT 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.

8

INSPECT FRONT ULTRASONIC SENSOR (LH) SIGNAL CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for 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.

9

INSPECT FRONT ULTRASONIC SENSOR (LH) 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 vehicle control module (VCM).
(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 front ultrasonic sensor (LH) and perform the repair completion verification.

(See FRONT ULTRASONIC SENSOR 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 vehicle control module (VCM).
(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 parking assist unit (ultrasonic), then go to the next step.
(See PARKING ASSIST UNIT (ULTRASONIC) REMOVAL/INSTALLATION.)

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	INSPECT VEHICLE CONTROL MODULE (VCM) AND BODY CONTROL MODULE (BCM) FOR MALFUNCTION • Perform the DTC inspection for the vehicle control module (VCM) and the body control module (BCM). (See DTC INSPECTION.) • Is any of the following DTCs displayed? ― DTC related to vehicle control module (VCM) and body control module (BCM) internal malfunction ― DTC related to parking assist unit (ultrasonic) internal malfunction ― DTC related to parking assist unit (ultrasonic) power supply malfunction (B14F4:16, B14F4:17)	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [VEHICLE CONTROL MODULE (E)].) (See DTC TABLE [BODY CONTROL MODULE (BCM) (E)].)
1		No	Go to the next step.
2	INSPECT PARKING ASSIST UNIT (ULTRASONIC) FOR MALFUNCTION • Perform the DTC inspection for the parking assist unit (ultrasonic). (See DTC INSPECTION.) • Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PARKING ASSIST UNIT (ULTRASONIC) (E)].)
2		No	Go to the next step.
3	VERIFY FRONT BUMPER EXTERNAL APPEARANCE AND INSTALLATION CONDITION • Verify the external appearance and installation condition of the applicable part. (See FRONT BUMPER REMOVAL/INSTALLATION [(E)].) • Are the external appearance and the installation condition normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location, or install the applicable part correctly and perform the repair completion verification. (See FRONT BUMPER REMOVAL/INSTALLATION [(E)].)
4	INSPECT FRONT ULTRASONIC SENSOR (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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT PARKING ASSIST UNIT (ULTRASONIC) 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 FRONT ULTRASONIC SENSOR (LH) 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 FRONT ULTRASONIC SENSOR (LH) SIGNAL CIRCUIT 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.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification.
8	INSPECT FRONT ULTRASONIC SENSOR (LH) SIGNAL CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
8		No	Repair or replace the malfunctioning location and perform the repair completion verification.
9	INSPECT FRONT ULTRASONIC SENSOR (LH) 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 vehicle control module (VCM). (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 front ultrasonic sensor (LH) and perform the repair completion verification. (See FRONT ULTRASONIC SENSOR 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 vehicle control module (VCM). (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 parking assist unit (ultrasonic), then go to the next step. (See PARKING ASSIST UNIT (ULTRASONIC) REMOVAL/INSTALLATION.)
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.