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DTC U2138:00 [VEHICLE CONTROL MODULE]

id1502c5048500

Outline

System malfunction location

Communication error with rear side radar sensor (LH)

Detection condition

•  The vehicle control module (VCM) detects that the rear side radar sensor (RH) cannot receive the CAN signal from the rear side radar sensor (LH) for 15 s.

Fail-safe

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

Possible cause

•  Rear side radar sensor (LH) connector or terminal malfunction

•  Short to ground or open circuit in rear side radar sensor (LH) power supply circuit

•  Open circuit in rear side radar sensor (LH) ground circuit

•  Rear side radar sensor (RH) connector or terminal malfunction

•  Short to ground in local CAN circuit

•  Short to power supply in local CAN circuit

•  Open circuit in local CAN circuit

•  Rear side radar sensor (LH) malfunction

•  Rear side radar sensor (RH) malfunction

•  Vehicle control module (VCM) malfunction (built into body control module (BCM))

System malfunction location	Communication error with rear side radar sensor (LH)
Detection condition	• The vehicle control module (VCM) detects that the rear side radar sensor (RH) cannot receive the CAN signal from the rear side radar sensor (LH) for 15 s.
Fail-safe	(See DTC TABLE [VEHICLE CONTROL MODULE (E)].)
Possible cause	• Rear side radar sensor (LH) connector or terminal malfunction • Short to ground or open circuit in rear side radar sensor (LH) power supply circuit • Open circuit in rear side radar sensor (LH) ground circuit • Rear side radar sensor (RH) connector or terminal malfunction • Short to ground in local CAN circuit • Short to power supply in local CAN circuit • Open circuit in local CAN circuit • Rear side radar sensor (LH) malfunction • Rear side radar sensor (RH) malfunction • Vehicle control module (VCM) malfunction (built into body control module (BCM))

Diagnostic Procedure

Step

Inspection

Results

Action

1

INSPECT REAR SIDE RADAR SENSOR (RH) FOR MALFUNCTION

•  Perform the DTC inspection for the rear side radar sensor (RH).
(See DTC INSPECTION.)

•  Is a DTC displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [REAR SIDE RADAR SENSOR (E)].)

No

Go to the next step.

2

INSPECT REAR SIDE RADAR SENSOR (LH) FOR MALFUNCTION

•  Perform the DTC inspection for the rear side radar sensor (LH).
(See DTC INSPECTION.)

•  Is a DTC displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [REAR SIDE RADAR SENSOR (E)].)

No

Go to the next step.

3

INSPECT REAR SIDE RADAR SENSOR (LH) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CIRCUIT 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 SIDE RADAR SENSOR (LH) POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT

•  Inspect the power supply 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.

5

INSPECT REAR SIDE RADAR SENSOR (LH) GROUND 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.

6

INSPECT REAR SIDE RADAR SENSOR (RH) CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CIRCUIT 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.

7

INSPECT LOCAL CAN 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.

8

INSPECT LOCAL CAN 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.

9

INSPECT LOCAL CAN 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.

10

INSPECT REAR SIDE RADAR 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 rear side radar sensor (LH) and perform the repair completion verification.

(See REAR SIDE RADAR SENSOR REMOVAL/INSTALLATION.)

No

Perform the [ACTION FOR NON-REPEATABLE MALFUNCTIONS].

(See TROUBLESHOOTING PROCEDURE [(E)].)

If DTC is displayed

•  Go to the next step.

If DTC is not displayed

•  Go to repair completion verification 2.

11

INSPECT REAR SIDE RADAR SENSOR (RH) 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 rear side radar sensor (RH) and perform the repair completion verification.

(See REAR SIDE RADAR SENSOR REMOVAL/INSTALLATION.)

No

Perform the [ACTION FOR NON-REPEATABLE MALFUNCTIONS].

(See TROUBLESHOOTING PROCEDURE [(E)].)

If DTC is displayed

•  Repeat the diagnosis from Step 1.

If DTC is not displayed

•  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 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	INSPECT REAR SIDE RADAR SENSOR (RH) FOR MALFUNCTION • Perform the DTC inspection for the rear side radar sensor (RH). (See DTC INSPECTION.) • Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [REAR SIDE RADAR SENSOR (E)].)
1		No	Go to the next step.
2	INSPECT REAR SIDE RADAR SENSOR (LH) FOR MALFUNCTION • Perform the DTC inspection for the rear side radar sensor (LH). (See DTC INSPECTION.) • Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [REAR SIDE RADAR SENSOR (E)].)
2		No	Go to the next step.
3	INSPECT REAR SIDE RADAR SENSOR (LH) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CIRCUIT 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 SIDE RADAR SENSOR (LH) POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT • Inspect the power supply circuit for a short to ground and open circuit. (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 SIDE RADAR SENSOR (LH) GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for open circuit. (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 REAR SIDE RADAR SENSOR (RH) CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CIRCUIT INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT LOCAL CAN 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.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification.
8	INSPECT LOCAL CAN 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.
8		No	Repair or replace the malfunctioning location and perform the repair completion verification.
9	INSPECT LOCAL CAN CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for open circuit. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
9		No	Repair or replace the malfunctioning location and perform the repair completion verification.
10	INSPECT REAR SIDE RADAR 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 rear side radar sensor (LH) and perform the repair completion verification. (See REAR SIDE RADAR SENSOR REMOVAL/INSTALLATION.)
10		No	Perform the [ACTION FOR NON-REPEATABLE MALFUNCTIONS]. (See TROUBLESHOOTING PROCEDURE [(E)].) If DTC is displayed • Go to the next step. If DTC is not displayed • Go to repair completion verification 2.
11	INSPECT REAR SIDE RADAR SENSOR (RH) 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 rear side radar sensor (RH) and perform the repair completion verification. (See REAR SIDE RADAR SENSOR REMOVAL/INSTALLATION.)
11		No	Perform the [ACTION FOR NON-REPEATABLE MALFUNCTIONS]. (See TROUBLESHOOTING PROCEDURE [(E)].) If DTC is displayed • Repeat the diagnosis from Step 1. If DTC is not displayed • 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 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.