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DTC U3000:4B [ELECTRONICALLY CONTROLLED BRAKE UNIT]

id0402c6013700

Outline

System malfunction location

Abnormal electronically controlled brake unit temperature

Detection condition

• The electronically controlled brake unit detects an abnormal high temperature in the electric parking brake drive circuit.

Fail-safe

Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)

Possible cause

• Electronically controlled brake unit malfunction

System wiring diagram

Not applicable

Connector diagram

Not applicable

System malfunction location	Abnormal electronically controlled brake unit temperature
Detection condition	• The electronically controlled brake unit detects an abnormal high temperature in the electric parking brake drive circuit.
Fail-safe	Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)
Possible cause	• Electronically controlled brake unit malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY IF ELECTRONICALLY CONTROLLED BRAKE UNIT TEMPERATURE WAS TEMPORARILY HIGH

•  Press down the electric parking brake switch, release the electric parking brake, and leave the vehicle for 30 min or more.

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the following procedure 3 times or more.

―  Pull up the electric parking brake switch to operate the electric parking brake.

―  Press down the electric parking brake switch to release the electric parking brake.

•  Perform the DTC inspection for the electronically controlled brake unit.
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Go to the next step.

No

System is normal. (Explain to the customer that the protection control was performed by repeatedly operating the electric parking brake.)

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the following procedure 3 times or more.

―  Pull up the electric parking brake switch to operate the electric parking brake.

―  Press down the electric parking brake switch to release the electric parking brake.

•  Perform the DTC inspection for the electronically controlled brake 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 electronically controlled brake unit, then go to the next step.
(See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].)

(See ELECTRONICALLY CONTROLLED BRAKE UNIT 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	VERIFY IF ELECTRONICALLY CONTROLLED BRAKE UNIT TEMPERATURE WAS TEMPORARILY HIGH • Press down the electric parking brake switch, release the electric parking brake, and leave the vehicle for 30 min or more. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the following procedure 3 times or more. ― Pull up the electric parking brake switch to operate the electric parking brake. ― Press down the electric parking brake switch to release the electric parking brake. • Perform the DTC inspection for the electronically controlled brake unit. (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Go to the next step.
1		No	System is normal. (Explain to the customer that the protection control was performed by repeatedly operating the electric parking brake.)
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the following procedure 3 times or more. ― Pull up the electric parking brake switch to operate the electric parking brake. ― Press down the electric parking brake switch to release the electric parking brake. • Perform the DTC inspection for the electronically controlled brake 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 electronically controlled brake unit, then go to the next step. (See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].) (See ELECTRONICALLY CONTROLLED BRAKE UNIT 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.