Dtc C1237/37 Speed Sensor Rotor Faulty

Brake. Camry. Acv40 Gsv40
Brake Control. Camry. Acv40 Gsv40

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK TIRES

INSPECT SPEED SENSOR AND SENSOR ROTOR SERRATIONS

RECONFIRM DTC

CHECK SPEED SENSOR ROTOR

CHECK SPEED SENSOR TIP

INSPECT EACH SPEED SENSOR

CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU TO EACH SPEED SENSOR)

RECONFIRM DTC

DTC C1237/37 Speed Sensor Rotor Faulty


DESCRIPTION

The skid control ECU measures the speed of each wheel by receiving signals from the speed sensor.
These signals are used for recognizing that all 4 wheels are operating properly.
Therefore, all wheel signals must be equal.

DTC No.
DTC Detecting Condition
Trouble Area
C1237/37
When any of the following is detected:
  1. Wheel speed difference between the wheels.
  2. Wheel sensor signal failure.
  3. ABS control continues for 60 sec. or more.
  1. Brake actuator assembly (skid control ECU)
  2. Speed sensor rotor (Front)
  3. Rear axle hub and bearing assembly
  4. Speed sensor
  5. Speed sensor circuit
  6. Tire and wheel size
  7. Tire deformation

WIRING DIAGRAM


Camry. Acv40 Gsv40.Brake Control.Anti-Lock Brake System. Dtc C1237/37 Speed Sensor Rotor Faulty


Camry. Acv40 Gsv40.Brake Control.Anti-Lock Brake System. Dtc C1237/37 Speed Sensor Rotor Faulty


INSPECTION PROCEDURE

HINT:
Check the condition of each related circuit connector before troubleshooting (CAMRY_ACV40 RM000000UZ301ZX.html).
1.CHECK TIRES

  1. Check the size and condition of all 4 tires (CAMRY_ACV40 RM000000X9A01NX_01_0001.html).

    HINT:
    This DTC is output when tire deformation or a difference in tire size is detected.
    OK:
    The diameters of all 4 tires and air pressure are the same.


NG
REPLACE TIRES SO THAT ALL 4 TIRES ARE THE SAME SIZE
OK


2.INSPECT SPEED SENSOR AND SENSOR ROTOR SERRATIONS


    Camry. Acv40 Gsv40.Brake Control.Anti-Lock Brake System. Dtc C1237/37 Speed Sensor Rotor Faulty

  1. Disconnect the skid control ECU connector.

  1. Connect the oscilloscope to each speed sensor terminal of the skid control ECU connector.

    Terminals:
    Connector
    		Circuit
    A25-5 (FL+) - A25-6 (FL-)
    		Front left speed sensor
    A25-10 (FR+) - A25-9 (FR-)
    		Front right speed sensor
    A25-7 (RL+) - A25-17 (RL-)
    		Rear left speed sensor
    A25-19 (RR+) - A25-8 (RR-)
    		Rear right speed sensor


    Camry. Acv40 Gsv40.Brake Control.Anti-Lock Brake System. Dtc C1237/37 Speed Sensor Rotor Faulty

  1. Check that a waveform is output when the tires are rotated (by the sensor circuit).

    OK:
    A waveform as shown in the figure should be output.
    HINT:
    1. Each sensor circuit outputs the same waveform without noise.
    2. As vehicle speed (wheel rotation speed) increases, the width of the waveform narrows and the output voltage becomes greater.
    3. When noise is identified in the waveform on the oscilloscope, the erratic signals are generated due to rotor scratches, looseness or foreign matter attached to the speed sensor.

  1. Make sure that the waveform does not change while jiggling a connector or a wire harness.

    OK:
    The waveform does not change.
    HINT:
    If the waveform changes while jiggling a connector or a wire harness, there may be a malfunction in the connector or the wire harness.

  1. Connect the connector.



NG
Go to step 4
OK


3.RECONFIRM DTC

  1. Clear the DTC (CAMRY_ACV40 RM000001JB800HX.html).

  1. Start the engine.

  1. Drive the vehicle at a speed of 32 km/h (20 mph) or more for 60 seconds or more.

  1. Check if the same DTC is recorded (CAMRY_ACV40 RM000001JB800HX.html).

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

    Result:

    Condition
    		Proceed to
    DTC is not output
    		A
    DTC is output
    		B


B
REPLACE BRAKE ACTUATOR ASSEMBLY (CAMRY_ACV40 RM0000013P6007X.html)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (CAMRY_ACV40 RM000001JB700GX.html)

4.CHECK SPEED SENSOR ROTOR

  1. Check the speed sensor rotor.
    Front Speed Sensor Rotor: (CAMRY_ACV40 RM000001JBG00GX.html)
    Rear Speed Sensor Rotor: (CAMRY_ACV40 RM000001JDB00GX.html)

    OK:
    No scratches or foreign matter on the rotors.
    NOTICE:
    Check the speed sensor signal after the cleaning/replacement (CAMRY_ACV40 RM000001JBD011X.html).


NG
CLEAN OR REPLACE SPEED SENSOR ROTOR
OK


5.CHECK SPEED SENSOR TIP

  1. Remove each speed sensor.

  1. Check the speed sensor tip.

    OK:
    No scratches or foreign matter on the sensor tip.
    NOTICE:
    Check the speed sensor signal after the cleaning/replacement (CAMRY_ACV40 RM000001JBD011X.html).

  1. Install the speed sensor.



NG
CLEAN OR REPLACE SPEED SENSOR
OK


6.INSPECT EACH SPEED SENSOR


    Camry. Acv40 Gsv40.Brake Control.Anti-Lock Brake System. Dtc C1237/37 Speed Sensor Rotor Faulty

  1. Disconnect each speed sensor connector.

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

    Standard resistance:
    FRONT:
    Tester Connection
    		Condition
    		Specified Condition
    A14-1 (FL+) - A14-2 (FL-)
    		Always
    		1.4 to 1.8 kΩ at 20°C (68°F)
    A14-1 (FL+) - Body ground
    		Always
    		10 kΩ or higher
    A14-2 (FL-) - Body ground
    		Always
    		10 kΩ or higher
    A35-1 (FR+) - A35-2 (FR-)
    		Always
    		1.4 to 1.8 kΩ at 20°C (68°F)
    A35-1 (FR+) - Body ground
    		Always
    		10 kΩ or higher
    A35-2 (FR-) - Body ground
    		Always
    		10 kΩ or higher
    REAR:
    Tester Connection
    		Condition
    		Specified Condition
    g1-1 (RL+) - g1-2 (RL-)
    		Always
    		Below 2.2 kΩ
    g1-1 (RL+) - Body ground
    		Always
    		10 kΩ or higher
    g1-2 (RL-) - Body ground
    		Always
    		10 kΩ or higher
    f1-1 (RR+) - f1-2 (RR-)
    		Always
    		Below 2.2 kΩ
    f1-1 (RR+) - Body ground
    		Always
    		10 kΩ or higher
    f1-2 (RR-) - Body ground
    		Always
    		10 kΩ or higher

  1. Connect the connector.

    NOTICE:
    Check the speed sensor signal after replacement (CAMRY_ACV40 RM000001JBD011X.html).


NG
REPLACE EACH SPEED SENSOR
OK


7.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU TO EACH SPEED SENSOR)


    Camry. Acv40 Gsv40.Brake Control.Anti-Lock Brake System. Dtc C1237/37 Speed Sensor Rotor Faulty

  1. Disconnect the skid control ECU connector.

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

    Standard resistance:
    FRONT:
    Tester Connection
    		Condition
    		Specified Condition
    A25-5 (FL+) - A14-1 (FL+)
    		Always
    		Below 1 Ω
    A25-6 (FL-) - A14-2 (FL-)
    		Always
    		Below 1 Ω
    A25-10 (FR+) - A35-1 (FR+)
    		Always
    		Below 1 Ω
    A25-9 (FR-) - A35-2 (FR-)
    		Always
    		Below 1 Ω
    A25-5 (FL+) - Body ground
    		Always
    		10 kΩ or higher
    A25-6 (FL-) - Body ground
    		Always
    		10 kΩ or higher
    A25-10 (FR+) - Body ground
    		Always
    		10 kΩ or higher
    A25-9 (FR-) - Body ground
    		Always
    		10 kΩ or higher
    REAR:
    Tester Connection
    		Condition
    		Specified Condition
    A25-7 (RL+) - g1-1 (RL+)
    		Always
    		Below 1 Ω
    A25-17 (RL-) - g1-2 (RL-)
    		Always
    		Below 1 Ω
    A25-19 (RR+) - f1-1 (RR+)
    		Always
    		Below 1 Ω
    A25-8 (RR-) - f1-2 (RR-)
    		Always
    		Below 1 Ω
    A25-7 (RL+) - Body ground
    		Always
    		10 kΩ or higher
    A25-17 (RL-) - Body ground
    		Always
    		10 kΩ or higher
    A25-19 (RR+) - Body ground
    		Always
    		10 kΩ or higher
    A25-8 (RR-) - Body ground
    		Always
    		10 kΩ or higher

  1. Connect the connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU TO EACH SPEED SENSOR)
OK


8.RECONFIRM DTC

  1. Clear the DTC (CAMRY_ACV40 RM000001JB800HX.html).

  1. Start the engine.

  1. Drive the vehicle at the speed of 32 km/h (20 mph) or more for at least 60 seconds.

  1. Check if the same DTC is recorded (CAMRY_ACV40 RM000001JB800HX.html).

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

    Result:

    Condition
    		Proceed to
    DTC (C1237/37) is not output
    		A
    DTC (C1237/37) is output
    		B


B
REPLACE BRAKE ACTUATOR ASSEMBLY (CAMRY_ACV40 RM0000013P6007X.html)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (CAMRY_ACV40 RM000001JB700GX.html)