BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (w/o Vacuum Brake Booster): C12F812,C12F814; ECB Solenoid Control "A" Circuit Short to Battery; 2022 - 2024 MY RAV4 RAV4 HV [12/2021

Last Modified: 01-30-2024	6.11:8.1.0	Doc ID: RM10000000214QD
Model Year Start: 2022	Model: RAV4	Prod Date Range: [12/2021 - ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (w/o Vacuum Brake Booster): C12F812,C12F814; ECB Solenoid Control "A" Circuit Short to Battery; 2022 - 2024 MY RAV4 RAV4 HV [12/2021 - ]

DTC

C12F812

ECB Solenoid Control "A" Circuit Short to Battery

DTC

C12F814

ECB Solenoid Control "A" Circuit Short to Ground or Open

DESCRIPTION

The main relay is built into the No. 1 skid control ECU (brake booster with master cylinder assembly).

The main relay supplies power to the switching solenoid and the linear solenoid.

The main relay remains on for approximately 4 minutes after the ignition switch is turned off and the input of brake pedal operation signals stops, and supplies power to the system to keep it ready to operate.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Note
C12F812	ECB Solenoid Control "A" Circuit Short to Battery	The BS terminal voltage is 3.5 V or more for 4.5 seconds or more, when operation of the main relay is requested.	Short in main relay circuit Main relay internal stuck Wire harness and connector No. 1 skid control ECU (brake booster with master cylinder assembly)	Comes on	SAE Code: C12FB Output ECU: Both skid control ECUs ECB: Electronically Controlled Brake System
C12F814	ECB Solenoid Control "A" Circuit Short to Ground or Open	Either of the following is detected: When the ignition switch is turned to ON (READY): The BS terminal voltage is less than 3.8 V for 0.05 seconds or more, when the IG1 terminal voltage is 9.5 V or more and operation of the main relay is requested. When the ignition switch is off: The BS terminal voltage is less than 3.8 V for 0.05 seconds or more, when operation of the main relay is requested.	Open or short in main relay circuit Wire harness and connector No. 1 skid control ECU (brake booster with master cylinder assembly)	Comes on	SAE Code: C12FA Output ECU: Both skid control ECUs ECB: Electronically Controlled Brake System

C12F814 DTC Detection Conditions

		Vehicle Condition
		Pattern 1	Pattern 2
Diagnosis Condition	When the ignition switch is turned to ON (READY)	○	-
	When the IG1 terminal voltage is 9.5 V or more	○	-
	When the ignition switch is off	-	○
Malfunction Status	The BS terminal voltage is less than 3.8 V and operation of the main relay is requested	○	○
Detection Time		0.05 seconds or more.	0.05 seconds or more.
Number of Trips		1 trip	1 trip

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.

MONITOR DESCRIPTION

The No. 2 skid control ECU (brake actuator assembly) monitors the voltage at BS terminal.

When the main relay is instructed to be on and the voltage at BS terminal is within the range of an open circuit malfunction (voltage is practically equal to that when off), or when the main relay is instructed to be off and the voltage of the BS terminal is within the range of a short circuit malfunction (voltage is practically equal to that when on), an open circuit or short circuit is judged respectively and the MIL is illuminated and stores a DTC.

MONITOR STRATEGY

Related DTCs	C12FA: Brake system voltage power supply relay open circuit C12FB: Brake system voltage power supply relay circuit high
Required Sensors/Components(Main)	No. 2 skid control ECU (brake actuator assembly)
Required Sensors/Components(Related)	No. 2 skid control ECU (brake actuator assembly)
Frequency of Operation	Continuous
Duration	0.054 seconds: C12FA (Case 1 and 2) 0.204 seconds: C12FA (Case 3) 4.5 seconds: C12FB
MIL Operation	Immediately
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

C12FA (Case 1)

Monitor runs whenever the following DTCs are not stored	C14C7 (Case 3 to 9): Brake system voltage circuit low
All of the following conditions are met	A, B, C and D
A. Ignition switch	Off
B. +BS (linear) effective invalidity	Valid
C. Command to brake pressure control solenoid power supply relay	On
D. Either of the following conditions is met	-
Brake system voltage 1	Higher than 7.3 V
Main relay on experience	Unavailable

C12FA (Case 2)

Monitor runs whenever the following DTCs are not stored	C14C7 (Case 3 to 9): Brake system voltage circuit low
All of the following conditions are met	A, B, C and D
A. Ignition switch	On (READY)
B. +BS (linear) effective invalidity	Valid
C. Command to brake pressure control solenoid power supply relay	On
D. Either of the following conditions is met	a or b
a. Both of the following conditions are met	-
Brake system voltage 1	Higher than 7.3 V
IG1 voltage	Higher than 9.5 V
b. Main relay on experience	Unavailable

C12FA (Case 3)

Monitor runs whenever the following DTCs are not stored	C14C7 (Case 3 to 9): Brake system voltage circuit low
Both of the following conditions are met	-
Solenoid relay	On
Brake system voltage 1	Higher than 7.3 V

C12FB (Case 1)

Monitor runs whenever the following DTCs are not stored	None
Both of the following conditions are met	-
+BS (linear) effective invalidity	Valid
Command to brake pressure control solenoid power supply relay	Off

C12FB (Case 2)

Monitor runs whenever the following DTCs are not stored	None
Solenoid relay	Off

TYPICAL MALFUNCTION THRESHOLDS

C12FA (Case 1 and 2)

Power supply for solenoid voltage

Less than 3.3 V

C12FA (Case 3)

Power supply for solenoid voltage

Less than 6.0 V

C12FB (Case 1)

Power supply for solenoid voltage

3.3 V or more

C12FB (Case 2)

Power supply for solenoid voltage

6.0 V or more

COMPONENT OPERATING RANGE

C12FA (Case 1 and 2) and C12FB (Case 1)

Both of the following conditions are met	A and B
A. All of the following conditions are met at the ECU status (last IG ON timing final)	-
Brake system voltage fail (C12FA, C12FB)	Not detected
Brake booster motor fail (C141C, C141D, C141E, C141F)	Not detected
Brake pressure control solenoid fail (C14F4, C14FD, C150A, C1510)	Not detected
B. All of the following conditions are met at the ECU status (pre main)	-
Brake system voltage fail (C121F, C12FA, C12FB)	Not detected
Brake booster motor fail (C141C)	Not detected
Brake pressure control solenoid fail (C14F3, C14F4, C14FC, C14FD, C1509, C150A, C150F, C1510)	Not detected

C12FA (Case 3)

All of the following conditions are met	A, B, C and D
A. Solenoid relay	On
B. Brake system voltage 1	Higher than 7.3 V
C. All of the following conditions are met at the ECU status (last IG ON timing final)	-
Brake system voltage fail (C12FA, C12FB)	Not detected
Brake booster motor fail (C141C, C141D, C141E, C141F)	Not detected
Brake pressure control solenoid fail (C14F4, C14FD, C150A, C1510)	Not detected
D. All of the following conditions are met at the ECU status (pre main)	-
Brake system voltage fail (C121F, C12FA, C12FB)	Not detected
Brake booster motor fail (C141C)	Not detected
Brake pressure control solenoid fail (C14F3, C14F4, C14FC, C14FD, C1509, C150A, C150F, C1510)	Not detected

C12FB (Case 2)

All of the following conditions are met	A, B and C
A. Solenoid relay	Off
B. All of the following conditions are met at the ECU status (last IG ON timing final)	-
Brake system voltage fail (C12FA, C12FB)	Not detected
Brake booster motor fail (C141C, C141D, C141E, C141F)	Not detected
Brake pressure control solenoid fail (C14F4, C14FD, C150A, C1510)	Not detected
C. All of the following conditions are met at the ECU status (pre main)	-
Brake system voltage fail (C121F, C12FA, C12FB)	Not detected
Brake booster motor fail (C141C)	Not detected
Brake pressure control solenoid fail (C14F3, C14F4, C14FC, C14FD, C1509, C150A, C150F, C1510)	Not detected

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 5 seconds 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/EPB / 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.

WIRING DIAGRAM

Refer to DTC C110E14.

Click here

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
After replacing the No. 1 skid control ECU (brake booster with master cylinder assembly), perform "Calibration" after performing "Reset Memory".
Click here

PROCEDURE

1.	PERFORM ACTIVE TEST USING GTS (MAIN RELAY)

(a) Perform the Active Test and operate the main relay.

(b) Monitor the value of BS Voltage when the Active Test is being performed.

Chassis > Brake Booster > Active Test

Tester Display

Measurement Item

Control Range

Restrict Condition

Diagnostic Note

ECB Main Relay

Main relay

OFF / ON

Vehicle condition: Vehicle stopped

HINT:

To protect this Actuator and Solenoid, this test will only last 5 seconds.

ECB: Electronically Controlled Brake System

Chassis > Brake Booster > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

BS Voltage

BS voltage value

Min.: 0.000 V

Max.: 20.000 V

Changes in proportion to auxiliary battery voltage

Chassis > Brake Booster > Active Test

Active Test Display
ECB Main Relay

Data List Display
BS Voltage

Result	Proceed to
During the Active Test, the voltage indicated by BS Voltage increases to the approximate voltage of the auxiliary battery.	A
During the Active Test, the voltage indicated by BS Voltage remains low around 0 V.	B

HINT:

During the Active Test, the voltage indicated by BS Voltage changes in proportion to the voltage of the auxiliary battery.

GO TO STEP 4

CLEAR DTC

(a) Clear the DTCs.

Chassis > Brake Booster > Clear DTCs

(b) Turn the ignition switch off.

3.	RECONFIRM DTC

(a) Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.

(b) Check if the same DTC is output.

Chassis > Brake Booster > Trouble Codes

Result	Proceed to
DTCs C12F812 and C12F814 are not output.	A
DTCs C12F812 and/or C12F814 are output.	B

USE SIMULATION METHOD TO CHECK

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

4.	CHECK HARNESS AND CONNECTOR (+BI1 TERMINAL)

(a) Turn the ignition switch off.

*a	Front view of wire harness connector (to No. 1 Skid Control ECU (Brake Booster with Master Cylinder Assembly))

(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.

OK:

The connector is securely connected.

(d) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

(e) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
A104-14 (+BI1) - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	CHECK HARNESS AND CONNECTOR (BS TERMINAL)

(a) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
A104-15 (BS) - Body ground	Always	11 to 14 V

*a	Front view of wire harness connector (to No. 1 Skid Control ECU (Brake Booster with Master Cylinder Assembly))

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR