VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1405, C1406

WIRING DIAGRAM

Refer to DTCs C1401 and C1402 (Click here).

INSPECTION PROCEDURE

PROCEDURE

1. Click here

   CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

   
   

   1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to the DTC (Click here).

      Table 1. ABS / VSC / TRC:

      Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
      FR Speed Open	FR speed sensor open detection / ERROR or NORMAL	ERROR: Momentary interruption NORMAL: Normal	-
      FL Speed Open	FL speed sensor open detection / ERROR or NORMAL	ERROR: Momentary interruption NORMAL: Normal	-

      OK
      There are no momentary interruptions.

      Tip:

      Perform the above inspection before removing the sensor and connector.

   
   
   • OKClick here
   • NGClick here
2. Click here

   READ VALUE ON INTELLIGENT TESTER (FRONT SPEED SENSOR)

   
   

   1. Turn the ignition switch off.

   2. Connect the intelligent tester to the DLC3.

   3. Start the engine.

   4. Select the Data List mode on the intelligent tester (Click here).

      Table 2. ABS / VSC / TRC:

      Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
      FR Wheel Speed	FR wheel speed sensor reading / min.: 0 km/h (0 mph), max.: 326 km/h (202 mph)	Actual wheel speed	Similar speed as indicated on speedometer
      FL Wheel Speed	FL wheel speed sensor reading /min.: 0 km/h (0 mph), max.: 326 km/h (202 mph)	Actual wheel speed	Similar speed as indicated on speedometer

   5. Check that there is no difference between the speed value output from the speed sensor displayed on the intelligent tester and the speed value displayed on the speedometer when driving the vehicle.

      Tip:

      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 intelligent tester is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).

   
   
   • OKClick here
   • NGClick here
3. Click here

   RECONFIRM DTC

   
   

   1. Turn the ignition switch off.

   2. Clear the DTCs (Click here).

   3. Start the engine.

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

   5. Check if the same DTC is recorded (Click here).

      Result
      Result Proceed to DTCs (C1405 and C1406) are not output A DTCs (C1405 and/or C1406) are output B

      Tip:

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

   
   
   • AClick here
   • BClick here
4. Click here

   CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)

   
   
   1. 

      Turn the ignition switch off.

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

   3. Disconnect the skid control ECU connector and the front speed sensor connector.

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

      Standard resistance
      for RH
      Tester Connection Condition Specified Condition A24-7 (FR+) - A25-2 (FR+) Always Below 1 Ω A24-7 (FR+) - Body ground Always 10 kΩ or higher A24-6 (FR-) - A25-1 (FR-) Always Below 1 Ω A24-6 (FR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition A24-19 (FL+) - A14-2 (FL+) Always Below 1 Ω A24-19 (FL+) - Body ground Always 10 kΩ or higher A24-18 (FL-) - A14-1 (FL-) Always Below 1 Ω A24-18 (FL-) - Body ground Always 10 kΩ or higher

   
   
   • OKClick here
   • NGClick here
5. Click here

   INSPECT SKID CONTROL ECU (SENSOR INPUT)

   
   
   1. 

      Reconnect the skid control ECU connector.

   2. Turn the ignition switch on (IG).

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

      Standard voltage
      for RH
      Tester Connection Switch Condition Specified Condition A25-2 (FR+) - Body ground Ignition switch on (IG) 8 to 14 V
      for LH
      Tester Connection Switch Condition Specified Condition A14-2 (FL+) - Body ground Ignition switch on (IG) 8 to 14 V

      Note:

      Check the speed sensor signal after replacement (Click here).

      Tip:

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

   
   
   • OKClick here
   • NGClick here
6. Click here

   CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)Click here

7. Click here

   REPLACE FRONT SPEED SENSORClick here

8. Click here

   REPLACE BRAKE ACTUATOR ASSEMBLYClick here

9. Click here

   REPAIR OR REPLACE HARNESS OR CONNECTOR