BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for HV Model): C12BF49,...,C12BF9E; Electronic Brake Booster Motor "A" Drive Circuit Internal Electronic Failure; 2023 - 2025 MY Corolla Corolla HV [09/2022

Last Modified: 07-31-2024	6.11:8.1.0	Doc ID: RM1000000025DUE
Model Year Start: 2023	Model: Corolla	Prod Date Range: [09/2022 - ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for HV Model): C12BF49,...,C12BF9E; Electronic Brake Booster Motor "A" Drive Circuit Internal Electronic Failure; 2023 - 2025 MY Corolla Corolla HV [09/2022 - ]

DTC

C12BF49

Electronic Brake Booster Motor "A" Drive Circuit Internal Electronic Failure

DTC

C12BF87

Electronic Brake Booster Motor "A" Drive Circuit Missing Message

DTC

C12BF96

Electronic Brake Booster Motor "A" Drive Circuit Component Internal Failure

DTC

C12BF9E

Electronic Brake Booster Motor "A" Drive Circuit Stuck On

DESCRIPTION

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

The electric brake booster (brake booster with master cylinder assembly) turns the motor relay on to operate the motor in the brake booster with master cylinder assembly in accordance with the operation angle of the brake pedal by the driver.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	DTC Output from	Note
C12BF49	Electronic Brake Booster Motor "A" Drive Circuit Internal Electronic Failure	Motor relay drive circuit abnormality detected.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12BF (Case 6) Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12BF87	Electronic Brake Booster Motor "A" Drive Circuit Missing Message	Motor relay drive circuit abnormality detected.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12BF (Case 9) Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12BF96	Electronic Brake Booster Motor "A" Drive Circuit Component Internal Failure	Motor relay internal abnormality detected.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12BF (Case 1 to 5 and 8) Output ECU: Electric brake booster (brake booster with master cylinder assembly)
C12BF9E	Electronic Brake Booster Motor "A" Drive Circuit Stuck On	Motor relay drive circuit low voltage detected.	Electric brake booster (brake booster with master cylinder assembly)	Comes on	Brake Booster	SAE Code: C12BF (Case 7) Output ECU: Electric brake booster (brake booster with master cylinder assembly)

MONITOR DESCRIPTION

C12BF (Case 1, 2 and 6):

When the electronically controlled brake system is starting and a motor drive circuit malfunction is detected, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12BF (Case 3, 4 and 5):

When the electronically controlled brake system is operating or shutting down and a motor drive circuit internal malfunction is detected, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12BF (Case 7):

When the electronically controlled brake system is starting, operating or shutting down, and the MOSFET voltage of the motor drive circuit is outside of a certain range, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12BF (Case 8):

When the electronically controlled brake system is starting or DTC conditions are met, the self-diagnosis function performs a motor test. If the motor test does not complete within a certain amount of time, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

C12BF (Case 9):

When the electronically controlled brake system is starting, operating or shutting down, and a motor drive circuit malfunction is detected, the electric brake booster (brake booster with master cylinder assembly) illuminates the MIL and stores this DTC.

MONITOR STRATEGY

Related DTCs	C12BF (Case 1): Motor drive circuit start up test C12BF (Case 2): Motor drive circuit unsupported configuration monitor C12BF (Case 3): Motor drive circuit internal failure monitor C12BF (Case 4): Motor drive circuit FET monitor C12BF (Case 5): Motor drive circuit unavailable C12BF (Case 6): Motor drive circuit FET failure detection circuit test C12BF (Case 7): Motor drive circuit phase short circuit test and monitor C12BF (Case 8): Motor drive circuit initial test timeout monitor C12BF (Case 9): Motor drive circuit serial peripheral interface communication 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)
Frequency of Operation	During initial checking
Duration	-: C12BF (Case 1, 3, 4, 6) 0.01 seconds: C12BF (Case 2 and 9) 0.03 seconds: C12BF (Case 7) 0.1 seconds: C12BF (Case 5) 0.505 seconds: C12BF (Case 8)
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.
Depress the brake pedal several times to operate the motor of the brake booster with master cylinder assembly.[*1]
Wait for 1 second or more. [*2]
HINT:

[*1] to [*2]: 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