RM38N0EC _54 Brake _111814 BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS _0503031 ELECTRONICALLY CONTROLLED BRAKE SYSTEM(for Gasoline Model) C

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS  ELECTRONICALLY CONTROLLED BRAKE SYSTEM(for Gasoline Model)  C137BA2  Brake System Control Module "A" System Voltage System Voltage Low  


DESCRIPTION

If a malfunction is detected in the power supply circuit, the skid control ECU (brake actuator assembly) stores this DTC and the fail-safe function prohibits ABS operation.

This DTC is stored when the +BS terminal voltage meets one of the DTC detection conditions due to a malfunction in the power supply or charging circuit such as the battery or alternator circuit, etc.

The DTC is cleared when the +BS terminal voltage returns to normal.

DTC No. Detection Item DTC Detection Condition Trouble Area DTC Output from Priority
C137BA2 Brake System Control Module "A" System Voltage System Voltage Low Any of the following is detected:
1.

The vehicle speed is 6 km/h (4 mph) or more and the +BS terminal voltage (soft low voltage) is less than 9.6 V for 1 second or more.

2.

The vehicle speed is 6 km/h (4 mph) or more and the +BS terminal voltage (hard low voltage) is less than 6.9 V for 1 second or more.

3.

The +BS terminal voltage is less than 6.7 V and the skid control ECU (brake actuator assembly) judges that power supply voltage is abnormal for 0.06 seconds or more.

4.

The vehicle speed is 15 km/h (9 mph) or more and the +BS terminal voltage is 9.6 V or more, the skid control ECU (brake actuator assembly) turns on more than one valve at the same time within a short period of time and the valve relay supply voltage drop exceeds the threshold.*

5.

When the system has started, the +BS terminal voltage is less than 5 V for 0.5 seconds or more.

6.

The +BS terminal voltage is less than 2.6 V for 0.2 seconds or more.


·

Wire harness or connector

·

Skid control ECU (brake actuator assembly)


Brake/EPB A

*: The skid control ECU (brake actuator assembly) monitors the resistance of the power source line at the +BS terminal. A malfunction is detected when an abnormality occurs in the +BS terminal wire harness or its connection and the skid control ECU (brake actuator assembly) determines that the wiring resistance at the +BS terminal exceeds the standard resistance.

WIRING DIAGRAM

C408683E28
1.938,1.146 3.063,1.427 1.125,0.281 10 false from Battery 3.667,1.333 4.792,1.615 1.125,0.281 10 false ABS NO. 1 5.667,1.031 5.979,1.229 0.313,0.198 10 false 1 5.677,2.813 5.99,3.01 0.313,0.198 10 false 46 5.969,1.156 6.385,1.396 0.417,0.24 10 false +BM 5.969,2.938 6.385,3.177 0.417,0.24 10 false GND1 4.26,3.979 4.719,4.177 0.458,0.198 10 false A40 4.25,4.146 7.156,4.51 2.906,0.365 10 false Skid Control ECU (Brake Actuator Assembly) 3.719,1.021 3.875,1.219 0.156,0.198 10 false 1 4.208,1.031 4.365,1.229 0.156,0.198 10 false 2 1.938,2.042 3.063,2.323 1.125,0.281 10 false from Battery 4.188,1.906 4.344,2.104 0.156,0.198 10 false 2 3.719,1.917 3.875,2.115 0.156,0.198 10 false 1 5.656,1.917 5.969,2.115 0.313,0.198 10 false 30 5.969,2.042 6.385,2.281 0.417,0.24 10 false +BS 3.688,2.229 5.177,2.583 1.49,0.354 10 false ABS NO. 2

CAUTION / NOTICE / HINT

NOTICE:
·

Inspect the fuses for circuits related to this system before performing the following procedure.

·

Before performing troubleshooting, make sure to confirm that the battery voltage is normal.

Click hereGeneral>INTRODUCTION>HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS>HOW TO PROCEED WITH TROUBLESHOOTING



PROCEDURE

1.CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

Procedure1

a.

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

OK:

The connector is securely connected.



Pre-procedure1

b.

Disconnect the A40 skid control ECU (brake actuator assembly) connector.


Procedure2

c.

Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.



Procedure3

d.

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

Standard Voltage:
Tester Connection Condition Specified Condition

Click Location & Routing(A40)Location & Routing

Click Connector(A40)Engine Compartment>Engine Room Main Wire / Transmission Wire>Brake Actuator Assembly

A40-30 (+BS) - Body ground Always 11 to 14 V


Result:
Proceed to
OK
NG



Post-procedure1

e.

None



OK

2.CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

Procedure1

a.

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

OK:

The connector is securely connected.



Pre-procedure1

b.

Disconnect the A40 skid control ECU (brake actuator assembly) connector.


Procedure2

c.

Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.



Procedure3

d.

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

Standard Voltage:
Tester Connection Condition Specified Condition

Click Location & Routing(A40)Location & Routing

Click Connector(A40)Engine Compartment>Engine Room Main Wire / Transmission Wire>Brake Actuator Assembly

A40-1 (+BM) - Body ground Always 11 to 14 V


Result:
Proceed to
OK
NG



Post-procedure1

e.

None



OK

REPLACE BRAKE ACTUATOR ASSEMBLY

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>BRAKE ACTUATOR (for Gasoline Model)>REMOVAL


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR