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DTC U300A:62 [DSC HU/CM]

id040262014300

Outline

System malfunction location

Ignition switch

Detection condition

•  The DSC HU/CM detects that the following do not correspond.

―  IG1 power supply condition received via CAN communication from body control module (BCM)

―  IG1 power supply condition determined from DSC HU/CM power supply circuit (IG1)

Fail-safe

Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”.(See DTC TABLE [DSC HU/CM (E)].)

Possible cause

•  IG1 relay No.2 malfunction

•  DSC HU/CM connector or terminals malfunction

•  F48 7.5 A fuse malfunction

•  Short to ground in DSC HU/CM power supply circuit (IG1)

•  Open circuit in DSC HU/CM power supply circuit (IG1)

•  Short to power supply circuit in DSC HU/CM power supply circuit (IG1)

•  DSC HU/CM malfunction

System malfunction location	Ignition switch
Detection condition	• The DSC HU/CM detects that the following do not correspond. ― IG1 power supply condition received via CAN communication from body control module (BCM) ― IG1 power supply condition determined from DSC HU/CM power supply circuit (IG1)
Fail-safe	Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”.(See DTC TABLE [DSC HU/CM (E)].)
Possible cause	• IG1 relay No.2 malfunction • DSC HU/CM connector or terminals malfunction • F48 7.5 A fuse malfunction • Short to ground in DSC HU/CM power supply circuit (IG1) • Open circuit in DSC HU/CM power supply circuit (IG1) • Short to power supply circuit in DSC HU/CM power supply circuit (IG1) • DSC HU/CM malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

INSPECT IG1 RELAY No.2 FOR MALFUNCTION

•  Inspect the IG1 relay No.2.
(See RELAY INSPECTION.)

•  Is the part normal?

Yes

Go to the next step.

No

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

(See RELAY LOCATION [(E)].))

)

2

INSPECT DSC HU/CM 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 F48 7.5 A FUSE

•  Remove the F48 7.5 A fuse.

•  Inspect the F48 7.5 A fuse.

•  Is the fuse normal?

Yes

Reinstall the F48 7.5 A fuse, then go to the next step.

No

Replace the F48 7.5 A fuse and perform the repair completion verification.

4

INSPECT DSC HU/CM POWER SUPPLY CIRCUIT (IG1) 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.

5

INSPECT DSC HU/CM POWER SUPPLY CIRCUIT (IG1) 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 DSC HU/CM POWER SUPPLY CIRCUIT (IG1) 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.

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 DSC HU/CM.
(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 DSC HU/CM, then go to the next step.
(See DSC HU/CM REMOVAL/INSTALLATION [L.H.D. (E)].)

(See DSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)

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 IG1 RELAY No.2 FOR MALFUNCTION • Inspect the IG1 relay No.2. (See RELAY INSPECTION.) • Is the part normal?	Yes	Go to the next step.
1		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See RELAY LOCATION [(E)].)) )
2	INSPECT DSC HU/CM 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 F48 7.5 A FUSE • Remove the F48 7.5 A fuse. • Inspect the F48 7.5 A fuse. • Is the fuse normal?	Yes	Reinstall the F48 7.5 A fuse, then go to the next step.
3		No	Replace the F48 7.5 A fuse and perform the repair completion verification.
4	INSPECT DSC HU/CM POWER SUPPLY CIRCUIT (IG1) 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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT DSC HU/CM POWER SUPPLY CIRCUIT (IG1) 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 DSC HU/CM POWER SUPPLY CIRCUIT (IG1) 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.
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 DSC HU/CM. (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 DSC HU/CM, then go to the next step. (See DSC HU/CM REMOVAL/INSTALLATION [L.H.D. (E)].) (See DSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)
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.