DTC    C1252/52    Brake Booster Pump Motor on Time Abnormally Long

DTC    C1253/53    Hydro Booster Pump Motor Relay Malfunction

for Preparation Click here


DESCRIPTION

The skid control ECU detects decreases in the accumulator pressure according to the data from the accumulator pressure sensor, and then starts and stops the pump motor by operating the motor relay.
The skid control ECU usually drives the motor (ABS MOTOR1) relay 1 for ECB control, and the motor (ABS MOTOR2) relay 2 for ABS control. If either is of them malfunctioning, the other will substitute.

DTC No.
INF Code
DTC Detection Condition
Trouble Area
C1252/52
130
Motor relay is on for at least 5 minute.
  1. ABS MOTOR1 relay
  2. ABS MOTOR2 relay
  3. Brake actuator assembly
C1253/53
132
Motor relay 1 coil is energized for at least 1 second when linear solenoid power source voltage (BS1) is 9.5 V or more and motor relay 1 is off.
  1. ABS MOTOR1 relay
  2. Wire harness or connector
↑
133
Motor relay 1 coil is not energized for at least 1 second when linear solenoid power source voltage (BS1) is 9.5 V or more and motor relay 1 is on.
↑
↑
134
When the linear solenoid power supply 1 (BS1) is 7 V or more, either of DI1 or DI2 voltage is 7 V or more, and the motor relay 1 is on, MTT input of less than 5.3 V continues for 1 second or more.
  1. ABS MOTOR1 relay
  2. Wire harness or connector
  3. Brake actuator pump motor
  4. Brake actuator pump motor circuit
↑
136
Motor relay 2 coil is energized for at least 1 second when linear solenoid power source voltage (BS2) is 9.5 V or more and motor relay 2 is off.
  1. ABS MOTOR2 relay
  2. Wire harness or connector
↑
137
Motor relay 2 coil is not energized for at least 1 second when linear solenoid power source voltage (BS2) is 9.5 V or more and motor relay 2 is on.
↑
↑
138
When the linear solenoid power supply 2 (BS2) is 7 V or more, either of DI1 or DI2 voltage is 7 V or more, and the motor relay 2 is on, MTT input of less than 5.3 V continues for 1 second or more.
  1. ABS MOTOR2 relay
  2. Wire harness or connector
  3. Brake actuator pump motor
  4. Brake actuator pump motor circuit
↑
140
MTT input is 3.5 V or more for at least 2 seconds when motor relay 1 and 2 are off.
  1. ABS MOTOR1 relay
  2. ABS MOTOR2 relay
  3. Brake actuator pump motor
  4. Brake actuator pump motor circuit

WIRING DIAGRAM


C109407E01


INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU or brake actuator assembly, perform initialization of linear solenoid valve and calibration (Click here).

1.INSPECT FUSE (ABS1, ABS2 AND ABS MOTOR FUSES)

  1. Remove the ABS1, ABS2 and ABS MOTOR fuses from the engine room R/B (J/B) No.1.

  1. Check the ABS1, ABS2 and ABS MOTOR fuses.

    Resistance:
    Below 1 Ω (Continuity)



NG
REPLACE FUSE (ABS1, ABS2 OR ABS MOTOR FUSE)
OK


2.PERFORM ACTIVE TEST BY INTELLIGENT TESTER (ECB MOTOR RELAY)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Select the ACTIVE TEST mode on the intelligent tester.

    ABS / VSC / TR(A)C: 
    Item (Display)
    		Measurement Item /
    Range (Display)
    		Normal Condition
    ECB Motor Relay
    		Turns ECB motor relay 1 ON / OFF
    		Operation of relay
    (clicking sound) and motor can be heard
    ECB Motor Relay 2
    		Turns ECB motor relay 2 ON / OFF
    		Operation of relay
    (clicking sound) and motor can be heard

  1. Check the operation sound of the ECB motor relay and motor when operating it with the intelligent tester.

    OK:
    The operation sound of the ECB motor relay and motor should be heard.



NG
Go to step 6
OK


3.INSPECT BRAKE ACTUATOR ASSEMBLY


    C112750E01

  1. Disconnect the brake actuator assembly connector.

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

    Resistance:
    LHD:
    Tester Connection
    		Specified Condition
    A16-2 (BM1) - A16-31 (GND1)
    		Below 10 Ω
    A16-1 (BM2) - A16-31 (GND1)
    		Below 10 Ω
    A16-2 (BM1) - A16-1 (BM2)
    		Below 1 Ω
    A16-31 (GND1) - A16-32 (GND2)
    		Below 1 Ω
    A16-2 (BM1) - A16-33 (MTT)
    		About 33 Ω
    A16-1 (BM2) - A16-33 (MTT)
    		About 33 Ω

    Resistance:
    RHD:
    Tester Connection
    		Specified Condition
    A16-31 (BM1) - A16-1 (GND1)
    		Below 10 Ω
    A16-32 (BM2) - A16-1 (GND1)
    		Below 10 Ω
    A16-31 (BM1) - A16-32 (BM2)
    		Below 1 Ω
    A16-1 (GND1) - A16-2 (GND2)
    		Below 1 Ω
    A16-31 (BM1) - A16-3 (MTT)
    		About 33 Ω
    A16-32 (BM2) - A16-3 (MTT)
    		About 33 Ω



NG
REPLACE BRAKE ACTUATOR ASSEMBLY
OK


4.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU TO BRAKE ACTUATOR ASSEMBLY)


    C112751E01

  1. Disconnect the skid control ECU connector and brake actuator assembly connector.

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

    Resistance:
    LHD:
    Tester Connection
    		Specified Condition
    A13-37 (MTT) - A16-33 (MTT)
    		Below 1 Ω
    A13-37 (MTT) - Body ground
    		10 kΩ or higher
    A16-31 (GND1) - Body ground
    		Below 1 Ω
    A16-32 (GND2) - Body ground
    		Below 1 Ω

    Resistance:
    RHD:
    Tester Connection
    		Specified Condition
    A13-37 (MTT) - A16-3 (MTT)
    		Below 1 Ω
    A13-37 (MTT) - Body ground
    		10 kΩ or higher
    A16-1 (GND1) - Body ground
    		Below 1 Ω
    A16-2 (GND2) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.READ VALUE OF INTELLIGENT TESTER (ACCUMULATOR PRESSURE SENSOR)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG).

  1. Select the DATA LIST mode on the intelligent tester.

    ABS / VSC / TR(A)C: 
    Item (Display)
    		Measurement Item /
    Range (Display)
    		Normal Condition
    Accumulator Sensor
    		Accumulator pressure sensor / min.: 0 V, max.: 5 V
    		Specified value: 2.6 to 3.8 V

  1. Depress the brake pedal 4 or 5 times to operate the pump motor, and check the output value on the intelligent tester with the motor stopped (not braking).

    OK:
    Accumulator pressure sensor voltage does not drop.



NG
REPLACE BRAKE ACTUATOR ASSEMBLY
OK


6.INSPECT ABS MOTOR RELAY


    C110686E01

  1. Remove the ABS MOTOR1 relay and ABS MOTOR2 relay.

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

    Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3 - 5
    		Always
    		10 kΩ or higher
    (No continuity)
    3 - 5
    		Apply B+ between terminal 1 and 2
    		Below 1 Ω
    (Continuity)



NG
REPLACE ABS MOTOR RELAY
OK


7.INSPECT ABS MOTOR RELAY (POWER SOURCE TERMINAL)


    C106615E02

  1. Remove the ABS MOTOR1 relay and ABS MOTOR2 relay.

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

    Voltage:
    Tester Connection
    		Specified Condition
    5 - Body ground
    		10 to 14 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
OK


8.CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY TO ENGINE ROOM R/B NO.3)


    C112753E01

  1. Disconnect the brake actuator assembly connector.

  1. Remove the ABS MOTOR1 relay and ABS MOTOR2 relay.

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

    Resistance:
    LHD:
    Tester Connection
    		Specified Condition
    A16-2 (BM1) - ABS MOTOR1 relay (3)
    		Below 1 Ω
    A16-1 (BM2) - ABS MOTOR2 relay (3)
    		Below 1 Ω

    Resistance:
    RHD:
    Tester Connection
    		Specified Condition
    A16-31 (BM1) - ABS MOTOR1 relay (3)
    		Below 1 Ω
    A16-32 (BM2) - ABS MOTOR2 relay (3)
    		Below 1 Ω

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

    Resistance:
    LHD:
    Tester Connection
    		Specified Condition
    A16-2 (BM1) - Body ground
    		10 kΩ or higher
    A16-1 (BM2) - Body ground
    		10 kΩ or higher

    Resistance:
    RHD:
    Tester Connection
    		Specified Condition
    A16-31 (BM1) - Body ground
    		10 kΩ or higher
    A16-32 (BM2) - Body ground
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


9.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU TO ENGINE ROOM R/B NO.3)


    C110763E03

  1. Disconnect the skid control ECU (A13, A15) connectors.

  1. Remove the ABS MOTOR1 relay and ABS MOTOR2 relay.

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

    Resistance:
    Tester Connection
    		Specified Condition
    A13-20 (MR1) -
    ABS MOTOR1 relay (2)
    		Below 1 Ω
    A13-36 (R1-) - ABS MOTOR1 relay (1)
    		Below 1 Ω
    A15-18 (R2-) - ABS MOTOR2 relay (1)
    		Below 1 Ω
    A15-32 (MR2) -
    ABS MOTOR2 relay (2)
    		Below 1 Ω

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

    Resistance:
    Tester Connection
    		Specified Condition
    A13-20 (MR1) - Body ground
    		10 kΩ or higher
    A13-36 (R1-) - Body ground
    		10 kΩ or higher
    A15-18 (R2-) - Body ground
    		10 kΩ or higher
    A15-32 (MR2) - Body ground
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


10.RECONFIRM DTC

  1. Clear the DTC (Click here).

  1. Turn the engine switch on (IG).

  1. Check if the same DTCs are recorded (Click here).

    HINT:
    Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.


    Result:

    Condition
    		Proceed To
    DTCs (C1252/52 and C1253/53) are not output
    		A
    DTCs (C1252/52 and C1253/53) are output
    		B



B
REPLACE SKID CONTROL ECU
A

END