ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1273/73, C1274/74, C1466/33, C1467/34

DESCRIPTION

The speed sensor detects wheel speed and sends signals to the skid control ECU. These signals are used for ABS control.

DTCs C1273/73 and C1274/74 can be cleared when the speed sensor sends a wheel speed signal or when Test Mode ends. DTCs C1273/73 and C1274/74 are output only in Test Mode.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

   1. Using the Techstream, check for any momentary interruptions in the wire harness and connector corresponding to a DTC Click here.

      ABS/VSC/TRAC

      Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
      RR Speed Open	Rear speed sensor RH open detection / Error or Normal	Error: Momentary interruption Normal: Normal	-
      RL Speed Open	Rear speed sensor LH open detection / Error or Normal	Error: Momentary interruption Normal: Normal	-

      OK
      There are no momentary interruptions.

      Tech Tips

      Perform the above inspection before removing the sensor and connector.

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

2. READ VALUE USING TECHSTREAM (REAR SPEED SENSOR)

   1. Select the Data List on the Techstream Click here.

      ABS/VSC/TRAC

      Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
      RR Wheel Speed	Rear speed sensor RH / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)	Vehicle stopped: 0 km/h (0 mph)	When driving at constant speed: No large fluctuations
      RL Wheel Speed	Rear speed sensor LH / Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)	Vehicle stopped: 0 km/h (0 mph)	When driving at constant speed: No large fluctuations

   2. Check the speed value output from the speed sensor displayed on the Techstream.

      Tech Tips

      Factors that affect the indicated vehicle speed include tire size, tire inflation, and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using a speedometer tester (calibrated chassis dynamometer). For details about testing and the margin of error, see the reference chart Click here.

      OK
      The speed value output from the speed sensor displayed on the Techstream is similar to the speed indicated on the speedometer.

   NG

   CHECK REAR SPEED SENSOR INSTALLATION Click here

   OK

3. PERFORM TEST MODE INSPECTION (SIGNAL CHECK)

   1. Turn the power switch off.

   2. Perform the sensor check in the Test Mode procedure Click here.

      OK
      All Test Mode DTCs are cleared.

   NG

   CHECK REAR SPEED SENSOR INSTALLATION Click here

   OK

4. RECONFIRM DTC

   1. Turn the power switch off.

   2. Clear the DTCs Click here.

   3. Turn the power switch on (READY).

   4. Perform a road test.

   5. Check if the same DTC is output Click here.

      Result
      Result Proceed to DTCs C1466/33 and C1467/34 are not output. A DTCs C1466/33 and/or C1467/34 are output. B

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.

   B

   REPLACE REAR AXLE HUB AND BEARING ASSEMBLY Click here

   A

   CHECK FOR INTERMITTENT PROBLEMS Click here

5. CHECK REAR SPEED SENSOR INSTALLATION

   1. Turn the power switch off.

      

   2. Check the speed sensor installation.

      OK
      There is no clearance between the sensor and rear axle carrier.

   NG

   INSTALL REAR SPEED SENSOR CORRECTLY Click here

   OK

6. CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)

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

      

   2. Disconnect the rear speed sensor connector and the skid control sensor wire.

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition h1-2 (RR+) - hO1-1 (RR+) Always Below 1 Ω h1-2 (RR+) - hO1-2 (RR-) Always 10 kΩ or higher h1-2 (RR+) - Body ground Always 10 kΩ or higher h1-1 (RR-) - hO1-2 (RR-) Always Below 1 Ω h1-1 (RR-) - hO1-1 (RR+) Always 10 kΩ or higher h1-1 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition i1-2 (RL+) - iN1-1 (RL+) Always Below 1 Ω i1-2 (RL+) - iN1-2 (RL-) Always 10 kΩ or higher i1-2 (RL+) - Body ground Always 10 kΩ or higher i1-1 (RL-) - iN1-2 (RL-) Always Below 1 Ω i1-1 (RL-) - iN1-1 (RL+) Always 10 kΩ or higher i1-1 (RL-) - Body ground Always 10 kΩ or higher

      Text in Illustration

      *A	for RH
      *B	for LH
      *a	Front view of skid control sensor wire
      *b	Front view of wire harness connector (to Sensor Side Connector)
      *c	Front view of wire harness connector (to Vehicle Side Connector)

      Note

      Check the speed sensor signal after replacement Click here.

   NG

   REPLACE SKID CONTROL SENSOR WIRE Click here

   OK

7. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - SKID CONTROL SENSOR WIRE)

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

   2. Disconnect the skid control ECU (brake booster with master cylinder assembly) connector.

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition A28-22 (RR+) - hO1-1 (RR+) Always Below 1 Ω A28-22 (RR+) - Body ground Always 10 kΩ or higher A28-9 (RR-) - hO1-2 (RR-) Always Below 1 Ω A28-9 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition A28-20 (RL+) - iN1-1 (RL+) Always Below 1 Ω A28-20 (RL+) - Body ground Always 10 kΩ or higher A28-7 (RL-) - iN1-2 (RL-) Always Below 1 Ω A28-7 (RL-) - Body ground Always 10 kΩ or higher

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

8. INSPECT SKID CONTROL ECU (SENSOR OUTPUT)

   1. Reconnect the skid control ECU (brake booster with master cylinder assembly) connector.

      

   2. Turn the power switch on (IG).

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

      Standard Voltage
      for RH
      Tester Connection Condition Specified Condition hO1-1 (RR+) - Body ground Power switch on (IG) 5.7 to 14 V
      for LH
      Tester Connection Condition Specified Condition iN1-1 (RL+) - Body ground Power switch on (IG) 5.7 to 14 V

      Text in Illustration

      *a	Front view of wire harness connector (to Skid Control Sensor Wire)

   NG

   REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here

   OK

9. RECONFIRM DTC

   1. Turn the power switch off.

   2. Reconnect the rear speed sensor connector and the skid control sensor wire.

   3. Clear the DTCs Click here.

   4. Turn the power switch on (READY).

   5. Perform a road test.

   6. Check if the same DTC is output Click here.

      Result
      Result Proceed to DTCs C1466/33 and/or C1467/34 are output. A DTCs C1466/33 and C1467/34 are not output. B

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.

   B

   CHECK FOR INTERMITTENT PROBLEMS Click here

   A

10. REPLACE REAR AXLE HUB AND BEARING ASSEMBLY

    1. Turn the power switch off.

    2. Replace the rear speed sensor rotor with rear speed sensor (rear axle hub and bearing assembly) Click here.

       Tech Tips

       The rear speed sensor rotor is incorporated into the rear axle hub and bearing assembly.

       If the rear speed sensor rotor needs to be replaced, replace the rear axle hub and bearing assembly with rear speed sensor.

       Note

       Check the speed sensor signal after replacement Click here.

    NEXT

11. RECONFIRM DTC

    1. Clear the DTCs Click here.

    2. Turn the power switch on (READY).

    3. Perform a road test.

    4. Check if the same DTC is output Click here.

       Result
       Result Proceed to DTCs C1466/33 and/or C1467/34 are output. A DTCs C1466/33 and C1467/34 are not output. B

       Tech Tips

       If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.

    B

    END

    A

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY Click here