ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1252/52, C1253/53

DTC Code DTC Name
C1252/52 Brake Booster Pump Motor on Time Abnormally Long
C1253/53 Pump Motor Relay Malfunction

DESCRIPTION

The skid control ECU assembly 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 ABS motor relay.

The skid control ECU assembly usually drives the ABS motor relay 1 for electronically controlled brake system control, and the ABS motor relay 2 for ABS control. If either of them is malfunctioning, the other will substitute.

DTC No. Detection Item INF Code DTC Detection Condition Trouble Area Note
C1252/52 Brake Booster Pump Motor on Time Abnormally Long 130 ABS motor relay is on for at least 3 minutes.

  • Short in pump motor circuit or pump motor monitor circuit

  • ABS motor relay stuck

  • Accumulator pressure sensor malfunction in brake actuator assembly

  • Brake fluid leaks

  • Brake booster pump assembly is deteriorated

 Electronically controlled brake system DTC
C1253/53 Pump Motor Relay Malfunction

134

138

140

  • INF Code: 134


    • MTT input is less than 3.5 V for at least 1 second or more when linear solenoid power source voltage 1 is 9.5 V or more, either of +BI1 or +BI2 voltage is 7 V or more, and ABS motor relay 1 is on.

  • INF Code: 138


    • MTT input is less than 3.5 V for at least 1 second or more when linear solenoid power source voltage 2 is 9.5 V or more, either of +BI1 or +BI2 voltage is 7 V or more, and ABS motor relay 2 is on.

  • INF Code: 140


    • MTT input is 3.5 V or more for at least 2 seconds when ABS motor relay 1 and 2 are off.

  • INF Code: 134


    • Improperly connected connector, deformation or corrosion of terminals

    • Open in ABS motor relay 1 internal circuit

    • Open or short in ABS motor relay 1 circuit

    • Open in pump motor circuit or pump motor monitor circuit

  • INF Code: 138


    • Improperly connected connector, deformation or corrosion of terminals

    • Open in ABS motor relay 2 internal circuit

    • Open or short in ABS motor relay 1 circuit

    • Open in pump motor circuit or pump motor monitor circuit

  • INF Code: 140


    • Short in ABS motor relay 1 circuit and ABS motor relay 2 circuit

    • Short in pump motor circuit or pump motor monitor circuit

 Electronically controlled brake system DTC
DTC No. Brake warning light / yellow (minor malfunction) code ABS warning light code Slip indicator light code Brake hold standby indicator light code
C1252 52 42 45 21
C1253 53 42 45 21

WIRING DIAGRAM

B000W3OE09

CAUTION / NOTICE / HINT

Note


  • When replacing the skid control ECU assembly or brake actuator assembly, perform initialization and calibration of the linear solenoid valve.

    Click here

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (ABS MOTOR RELAY)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Select the Active Test on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      ECB Motor Relay ABS motor relay 1 Relay ON/OFF

      • Operation sound of relay (clicking sound) and pump motor can be heard

      • ECB: Electronically Controlled Brake System
      ECB Motor Relay2 ABS motor relay 2 Relay ON/OFF

      • Operation sound of relay (clicking sound) and pump motor can be heard

      • ECB: Electronically Controlled Brake System

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      ECB Motor Relay

      • ECB: Electronically Controlled Brake System


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      ECB Motor Relay2

      • ECB: Electronically Controlled Brake System

    4. Check the operation sound of the ABS motor relay and motor when operating it using the GTS.

      OK
      The operation sound of the ABS motor relay and motor should be heard.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT ABS MOTOR RELAY Click here

    OK

  2. INSPECT BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY


    1. B000Z7XC21
      *a

      Component without harness connected

      (Brake Booster with Accumulator Pump Assembly)

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

    2. Disconnect the A48 and A49 brake booster with accumulator pump assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A48-2 (BM1) - A48-4 (GND1) Always Below 10 Ω
      A49-2 (BM2) - A49-1 (GND2) Always Below 10 Ω
      A48-2 (BM1) - A49-2 (BM2) Always Below 1 Ω
      A48-4 (GND1) - A49-1 (GND2) Always Below 1 Ω
      A48-2 (BM1) - A48-1 (MTT) Always 950 to 1050 Ω
      A49-2 (BM2) - A48-1 (MTT) Always 950 to 1050 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU ASSEMBLY - BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY)


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

    2. Disconnect the A8 skid control ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A8-29 (MTT) - A48-1 (MTT) Always Below 1 Ω
      A8-29 (MTT) or A48-1 (MTT) - Body ground Always 10 kΩ or higher
      A48-4 (GND1) - Body ground Always Below 1 Ω
      A49-1 (GND2) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. READ VALUE USING GTS (ACCUMULATOR PRESSURE SENSOR)


    1. Reconnect the A8 skid control ECU assembly connector.

    2. Reconnect the A48 and A49 brake booster with accumulator pump assembly connectors.

    3. Connect the GTS to the DLC3.

    4. Turn the engine switch on (IG).

    5. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Accumulator Sensor Accumulator pressure sensor Min.: 0.00 V, Max.: 5.00 V Specified value: 2.60 to 3.80 V When brake fluid is stored in the accumulator: Accumulator pressure changes in accordance with volume of fluid stored in the accumulator

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Accumulator Sensor

    6. Depress the brake pedal 4 or 5 times and operate the pump motor.

    7. Wait for 30 seconds without depressing the brake pedal.

    8. Check that the accumulator pressure sensor output value change is within the specified range.

      OK
      Accumulator pressure sensor output value change is less than 0.20 V.

      Tech Tips


      • This inspection is performed to determine if a long-term power malfunction occurred when low pressure is detected due to a defective sensor, an internal leak in the brake actuator assembly, or deterioration of the accumulator.

      • External brake fluid leaks are suspected if the fluid level drops inside the brake master cylinder reservoir assembly.

      Result
      Proceed to
      OK
      NG

    NG

    PERFORM ACTIVE TEST USING GTS (SOLENOID VALVE) Click here

    OK

  5. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the engine switch off.

    3. Turn the engine switch on (IG).

    4. Check if the same DTC is output.

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Result Proceed to
      DTCs C1252/52 and C1253/53 are not output. A
      DTCs C1252/52 and/or C1253/53 are output. B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE SKID CONTROL ECU ASSEMBLY for RHD: Click here
    REPLACE SKID CONTROL ECU ASSEMBLY for LHD: Click here

  6. PERFORM ACTIVE TEST USING GTS (SOLENOID VALVE)


    1. Select the Active Test on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      ECB Solenoid (SMC1) Master cut solenoid (SMC1) Solenoid ON/OFF ECB: Electronically Controlled Brake System

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      ECB Solenoid (SMC1)

      • ECB: Electronically Controlled Brake System

      Tech Tips

      The Active Test can be performed when the following conditions are met.


      • ABS main relay is on.

      • Shift position is in P.

      • Parking brake is applied.

      • Vehicle speed is 0 km/h (0 mph).

    2. Perform the Active Test of the solenoid using the GTS.

    3. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FR W/C Sensor Front wheel cylinder pressure sensor RH Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.30 to 0.70 V Reading increases when brake pedal is depressed

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      FR W/C Sensor

    4. Check that the output value of the wheel cylinder pressure sensor does not increase.

      OK
      The output value of the wheel cylinder pressure sensor does not increase.

      Tech Tips

      If output value increases, there may be brake fluid leaks in the brake actuator assembly.

      Result
      Result Proceed to
      The output values of the wheel cylinder pressure sensors do not increase. A
      The output value of the wheel cylinder pressure sensor increases. B

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here

    A

  7. PERFORM ACTIVE TEST USING GTS (SOLENOID VALVE)


    1. Select the Active Test on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      ECB Solenoid (SMC2) Master cut solenoid (SMC2) Solenoid ON/OFF ECB: Electronically Controlled Brake System

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      ECB Solenoid (SMC2)

      • ECB: Electronically Controlled Brake System

      Tech Tips

      The Active Test can be performed when the following conditions are met.


      • ABS main relay is on.

      • Shift position is in P.

      • Parking brake is applied.

      • Vehicle speed is 0 km/h (0 mph).

    2. Perform the Active Test of the solenoid using the GTS.

    3. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FL W/C Sensor Front wheel cylinder pressure sensor LH Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.30 to 0.70 V Reading increases when brake pedal is depressed

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      FL W/C Sensor

    4. Check that the output value of the wheel cylinder pressure sensor does not increase.

      OK
      The output value of the wheel cylinder pressure sensor does not increase.

      Tech Tips

      If output value increases, there may be brake fluid leaks in the brake actuator assembly.

      Result
      Result Proceed to
      The output values of the wheel cylinder pressure sensors do not increase. A
      The output value of the wheel cylinder pressure sensor increases. B

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here

    A

  8. PERFORM ACTIVE TEST USING GTS (SOLENOID VALVE)


    1. Select the Active Test on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      ECB Solenoid (SLRRR) Linear solenoid (RRR) valve Valve close ON/OFF ECB: Electronically Controlled Brake System

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      ECB Solenoid (SLRRR)

      • ECB: Electronically Controlled Brake System

      Tech Tips

      The Active Test can be performed when the following conditions are met.


      • ABS main relay is on.

      • Shift position is in P.

      • Parking brake is applied.

      • Vehicle speed is 0 km/h (0 mph).

    2. Perform the Active Test of the solenoid using the GTS.

    3. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      RR W/C Sensor Rear wheel cylinder pressure sensor RH Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.30 to 0.70 V Reading increases when brake pedal is depressed

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      RR W/C Sensor

    4. Check that the output value of the wheel cylinder pressure sensor does not increase.

      OK
      The output value of the wheel cylinder pressure sensor does not increase.

      Tech Tips

      If output value increases, there may be brake fluid leaks in the brake actuator assembly.

      Result
      Result Proceed to
      The output values of the wheel cylinder pressure sensors do not increase. A
      The output value of the wheel cylinder pressure sensor increases. B

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here

    A

  9. PERFORM ACTIVE TEST USING GTS (SOLENOID VALVE)


    1. Select the Active Test on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      ECB Solenoid (SLRRL) Linear solenoid (RLR) valve Valve close ON/OFF ECB: Electronically Controlled Brake System

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      ECB Solenoid (SLRRL)

      • ECB: Electronically Controlled Brake System

      Tech Tips

      The Active Test can be performed when the following conditions are met.


      • ABS main relay is on.

      • Shift position is in P.

      • Parking brake is applied.

      • Vehicle speed is 0 km/h (0 mph).

    2. Perform the Active Test of the solenoid using the GTS.

    3. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      RL W/C Sensor Rear wheel cylinder pressure sensor LH Min.: 0.00 V, Max.: 5.00 V Brake pedal released: 0.30 to 0.70 V Reading increases when brake pedal is depressed

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      RL W/C Sensor

    4. Check that the output value of the wheel cylinder pressure sensor does not increase.

      OK
      The output value of the wheel cylinder pressure sensor does not increase.

      Tech Tips

      If output value increases, there may be brake fluid leaks in the brake actuator assembly.

      Result
      Result Proceed to
      The output values of the wheel cylinder pressure sensors do not increase. A
      The output value of the wheel cylinder pressure sensor increases. B

    A

    REPLACE BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY Click here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here

  10. INSPECT ABS MOTOR RELAY


    1. B000XX5C17
      *1 ABS Motor Relay (ABS MTR NO. 1 or ABS MTR NO. 2 relay)

      Remove the ABS motor relay (ABS MTR NO. 1 and ABS MTR NO. 2 relays).

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 - 5 Voltage is not applied between terminals 1 and 2 10 kΩ or higher
      3 - 5 Voltage is applied between terminals 1 and 2 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE ABS MOTOR RELAY

    OK

  11. INSPECT NO. 1 ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK (POWER SOURCE TERMINAL)


    1. Figure 1. for RHD:

      B000TUSC01
      *1 NO. 1 Engine Room Relay Block and Junction Block
      *2 ABS MTR NO. 1 Relay
      *3 ABS MTR NO. 2 Relay

      Figure 2. for LHD:

      B000TWBC01
      *1 NO. 1 Engine Room Relay Block and Junction Block
      *2 ABS MTR NO. 1 Relay
      *3 ABS MTR NO. 2 Relay

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      ABS MTR NO. 1 relay terminal 5 - Body ground Always 11 to 14 V
      ABS MTR NO. 2 relay terminal 5 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

    OK

  12. CHECK HARNESS AND CONNECTOR (BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY - NO. 1 ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK)


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

    2. Disconnect the A48 and A49 brake booster with accumulator pump assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A48-2 (BM1) - ABS MTR NO. 1 relay terminal 3 Always Below 1 Ω
      A48-2 (BM1) or ABS MTR NO. 1 relay terminal 3 - Body ground Always 10 kΩ or higher
      A49-2 (BM2) - ABS MTR NO. 2 relay terminal 3 Always Below 1 Ω
      A49-2 (BM2) or ABS MTR NO. 2 relay terminal 3 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU ASSEMBLY - NO. 1 ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK)


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

    2. Disconnect the A11 and A8 skid control ECU assembly connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A8-24 (R1-) - ABS MTR NO. 1 relay terminal 2 Always Below 1 Ω
      A8-24 (R1-) or ABS MTR NO. 1 relay terminal 2 - Body ground Always 10 kΩ or higher
      A8-11 (MR1) - ABS MTR NO. 1 relay terminal 1 Always Below 1 Ω
      A8-11 (MR1) or ABS MTR NO. 1 relay terminal 1 - Body ground Always 10 kΩ or higher
      A11-14 (R2-) - ABS MTR NO. 2 relay terminal 2 Always Below 1 Ω
      A11-14 (R2-) or ABS MTR NO. 2 relay terminal 2 - Body ground Always 10 kΩ or higher
      A11-17 (MR2) - ABS MTR NO. 2 relay terminal 1 Always Below 1 Ω
      A11-17 (MR2) or ABS MTR NO. 2 relay terminal 1 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE SKID CONTROL ECU ASSEMBLY for RHD: Click here
    REPLACE SKID CONTROL ECU ASSEMBLY for LHD: Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR