VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1273, C1274, C1277, C1278, C1415, C1416

DESCRIPTION

Each speed sensor detects the wheel speed and sends signals to the skid control ECU (brake actuator assembly). These signals are used by the ABS control system.

The speed sensor rotors have rows of alternating N and S magnetic poles. Hall IC type speed sensors use the frequency of output pulses to detect the vehicle speed. Because the sensor outputs digital pulses, it can detect the vehicle speed even when the vehicle is nearly stationary.

DTCs C1273 and C1274 are cleared when the speed sensor sends a vehicle speed signal or when Test Mode ends. DTCs C1273 and C1274 are output only in Test Mode.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

   
   

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

      ABS/VSC/TRC

      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

   CHECK REAR SPEED SENSOR INSTALLATION Click here

   OK

2. READ VALUE USING GTS (REAR SPEED SENSOR)

   
   

   1. Turn the engine switch off.

   2. Connect the GTS to the DLC3.

   3. Start the engine.

   4. Select the Data List using the GTS Click here.

      ABS/VSC/TRC

      Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
      RR Wheel Speed	Rear wheel speed sensor RH reading / 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 wheel speed sensor LH reading / 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

   5. Check the speed value output from the speed sensor displayed on the GTS.

      Tech Tips

      Factors that affect the indicated vehicle speed include tire size, tire pressure, 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 GTS is similar to the speed indicated on the speedometer.

   
   

   NG

   CHECK REAR SPEED SENSOR INSTALLATION Click here

   OK

3. RECONFIRM DTC

   
   

   1. Turn the engine switch off.

   2. Clear the DTCs Click here.

   3. Turn the engine switch off.

   4. Start the engine.

   5. Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

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

      Result
      Result Proceed to DTCs C1415 and C1416 are not output. A DTCs C1415 and/or C1416 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 before replacing parts Click here.

   
   

   B

   REPLACE BRAKE ACTUATOR ASSEMBLY Click here

   A

   USE SIMULATION METHOD TO CHECK Click here

4. CHECK REAR SPEED SENSOR INSTALLATION

   
   

   1. 

      Turn the engine 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

5. INSPECT SKID CONTROL SENSOR WIRE

   
   
   1. 

      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)

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

   2. Remove 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 b1-2 (RR+) - bQ2-1 (RR+) Always Below 1 Ω b1-2 (RR+) - bQ2-2 (RR-) Always 10 kΩ or higher b1-2 (RR+) - Body ground Always 10 kΩ or higher b1-1 (RR-) - bQ2-2 (RR-) Always Below 1 Ω b1-1 (RR-) - bQ2-1 (RR+) Always 10 kΩ or higher b1-1 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition b2-2 (RL+) - bP2-1 (RL+) Always Below 1 Ω b2-2 (RL+) - bP2-2 (RL-) Always 10 kΩ or higher b2-2 (RL+) - Body ground Always 10 kΩ or higher b2-1 (RL-) - bP2-2 (RL-) Always Below 1 Ω b2-1 (RL-) - bP2-1 (RL+) Always 10 kΩ or higher b2-1 (RL-) - Body ground Always 10 kΩ or higher

      Note

      Check the speed sensor signal after replacement Click here.

   
   

   NG

   REPLACE SKID CONTROL SENSOR WIRE Click here

   OK

6. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - 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 A40 skid control ECU (brake actuator assembly) connector.

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition A40-17 (RR+) - bQ2-1 (RR+) Always Below 1 Ω A40-17 (RR+) - Body ground Always 10 kΩ or higher A40-16 (RR-) - bQ2-2 (RR-) Always Below 1 Ω A40-16 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition A40-5 (RL+) - bP2-1 (RL+) Always Below 1 Ω A40-5 (RL+) - Body ground Always 10 kΩ or higher A40-4 (RL-) - bP2-2 (RL-) Always Below 1 Ω A40-4 (RL-) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

7. INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR INPUT)

   
   
   1. 

      Text in Illustration

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

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

   2. Turn the engine 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 bQ2-1 (RR+) - Body ground Engine switch on (IG) 8 to 14 V
      for LH
      Tester Connection Condition Specified Condition bP2-1 (RL+) - Body ground Engine switch on (IG) 8 to 14 V

      Note

      Check the speed sensor signal after replacement 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.

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

   
   

   NG

   REPLACE BRAKE ACTUATOR ASSEMBLY Click here

   OK

   REPLACE REAR AXLE HUB AND BEARING ASSEMBLY WITH REAR SPEED SENSOR Click here