Toyota Corolla Cross: Electronic Brake Booster Motor "A" (C12B400,C12B41C,C12B41E,C12B477,C12B496,C12B579)

Toyota Corolla Cross (2022-2024) Service Manual / Brake / Brake Control / Dynamic Control Systems / Electronically Controlled Brake System (for Hev Model) / Electronic Brake Booster Motor "A" (C12B400,C12B41C,C12B41E,C12B477,C12B496,C12B579)

DESCRIPTION

The motor actuator is built into the brake booster with master cylinder assembly.

The electric brake booster (brake booster with master cylinder assembly) drives the motor in accordance with the operation angle of the brake pedal by the driver to assist the brake pedal force of the driver.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	DTC Output from	Note
C12B400	Electronic Brake Booster Motor "A"	Abnormality in motor actuator rotation is detected for 0.3 seconds or more.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12B4 (Case 3) Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12B41C	Electronic Brake Booster Motor "A" Circuit Voltage Out of Range	Poor internal condition of motor actuator is detected.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12B4 (Case 4) Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12B41E	Electronic Brake Booster Motor "A" Circuit Resistance Out of Range	Internal failure in motor actuator is detected for 0.12 seconds.	Electric brake booster (brake booster with master cylinder assembly)	Does not come on	Brake Booster	Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12B477	Electronic Brake Booster Motor "A" Commanded Position Not Reachable	Abnormality in motor actuator rotation is detected for 0.3 seconds or more.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12B4 (Case 2) Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12B496	Electronic Brake Booster Motor "A" Component Internal Failure	Detected that the motor actuator cannot be driven.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12B4 (Case 1) Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12B579	Electronic Brake Booster Motor "A" Mechanical Linkage Failure	Abnormality in motor actuator rotation is detected.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12B5 (Case 1 and 2) Output ECU: Electric brake booster (brake booster with master cylinder assembly)

MONITOR DESCRIPTION

C12B4 (Case 1):

If the difference between the target angle of the pump motor and actual angle of the pump motor is more than a certain value, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12B4 (Case 2):

If there is an abnormal difference between the target rotation speed of the pump motor and actual rotation speed of the pump motor, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12B4 (Case 3):

If there is an abnormal difference between the brake pedal stroke amount detected by the differential travel sensor and the target stroke amount, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12B4 (Case 4):

If the difference between the target drive voltage and actual drive voltage of the pump motor is more than a certain value, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12B5 (Case 1):

If the spindle position inside the brake booster with master cylinder assembly is outside of a certain range, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12B5 (Case 2):

After self-diagnosis is performed, if the spindle position inside the brake booster with master cylinder assembly is not suitable or the spindle position cannot be detected after a certain amount of time has elapsed, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

MONITOR STRATEGY

Related DTCs	C12B4 (Case 1): Motor test C12B4 (Case 2): Motor rotation angle sensor rationality monitor (rotation speed) C12B4 (Case 3): Relative displacement rationality monitor C12B4 (Case 4): Motor voltage rationality monitor C12B5 (Case 1): Spindle position range monitor C12B5 (Case 2): Reference run monitor
Required Sensors/Components(Main)	Electric brake booster (brake booster with master cylinder assembly)
Required Sensors/Components(Related)	Electric brake booster (brake booster with master cylinder assembly) Speed sensor
Frequency of Operation	During initial checking
Duration	-: C12B5 (Case 2) 0.01 seconds: C12B4 (Case 1) 0.02 seconds: C12B4 (Case 4) 0.3 seconds: C12B4 (Case 2 and 3) More than 0.56 seconds (in case of MAX motor speed): C12B5 (Case 1)
MIL Operation	Immediately
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored	TMC's intellectual property
Other conditions belong to TMC's intellectual property	-

TYPICAL MALFUNCTION THRESHOLDS

TMC's intellectual property

COMPONENT OPERATING RANGE

TMC's intellectual property

CONFIRMATION DRIVING PATTERN

NOTICE:

When performing the normal judgment procedure, make sure that the driver door is closed and is not opened at any time during the procedure.

HINT:

After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the ignition switch off.
Turn the ignition switch to ON (READY) and turn the GTS on.
Wait for 1 second or more. [*]
HINT:

[*]: Normal judgment procedure.

The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
Enter the following menus: Chassis / Brake Booster / Utility / All Readiness.
Check the DTC judgment result.
HINT:
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE, perform driving pattern again.

PROCEDURE

1.	REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

Click here

END

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Toyota Corolla Cross: Electronic Brake Booster Motor "A" (C12B400,C12B41C,C12B41E,C12B477,C12B496,C12B579)

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