DTC U3000:54 [ELECTRONICALLY CONTROLLED BRAKE UNIT]

System malfunction location	Electric parking brake motor gear unit position learning not completed
Detection condition	• After replacing the electronically controlled brake unit, it detects that the electric parking brake motor gear unit position learning was not implemented.
Fail-safe	Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)
Possible cause	Caution • After replacing the electronically controlled brake unit, if the electric parking brake has never been operated/released, a DTC may be output. After replacing the electronically controlled brake unit, operate/release the electric parking brake and have the system learn the electric parking brake motor gear unit position. • Electronically controlled brake unit internal malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable

System malfunction location

Electric parking brake motor gear unit position learning not completed

Detection condition

• After replacing the electronically controlled brake unit, it detects that the electric parking brake motor gear unit position learning was not implemented.

Fail-safe

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

Possible cause

Caution

• After replacing the electronically controlled brake unit, if the electric parking brake has never been operated/released, a DTC may be output. After replacing the electronically controlled brake unit, operate/release the electric parking brake and have the system learn the electric parking brake motor gear unit position.

• Electronically controlled brake unit internal malfunction

System wiring diagram

Not applicable

Connector diagram

Not applicable

Step	Inspection	Results	Action
1	ELECTRIC PARKING BRAKE MOTOR GEAR UNIT POSITION LEARNING • 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. • 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, replace the electronically controlled brake unit and perform the repair completion verification. (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	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

ELECTRIC PARKING BRAKE MOTOR GEAR UNIT POSITION LEARNING

• 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.

• 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, replace the electronically controlled brake unit and perform the repair completion verification.

(See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].)

(See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [R.H.D.].)

Go to the next step.

Repair completion verification

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.

DTC troubleshooting completed.

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