DTC C1464/31: Front Speed Sensor RH Circuit; DTC C1271/71: Low Output Signal of Front Speed Sensor RH (Test Mode DTC); DTC C1272/72: Low Output Signal of Front Speed Sensor LH (Test Mode DTC); DTC C1465/32: Front Speed Sensor LH Circuit: Procedure

1. Using the Techstream, check for any momentary interruptions in the wire harness and connector corresponding to a DTC, refer to CHECK FOR INTERMITTENT PROBLEMS .
   ABS/VSC/TRAC
   
   

   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.

   HINT: 

   Perform the above inspection before removing the sensor and connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Select the Data List on the Techstream, refer to DATA LIST / ACTIVE TEST .
   ABS/VSC/TRAC
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   FR Wheel Speed	FR wheel speed sensor / 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
   FL Wheel Speed	FL wheel speed sensor / 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.

   HINT: 

   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 Reference Chart, refer to ON-VEHICLE INSPECTION .

   OK

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

NG → See step   5 

OK: Go to next step 

1. Turn the ignition switch off.
2. Perform the sensor check in the Test Mode procedure, refer to TEST MODE PROCEDURE .

   OK

   All Test Mode DTCs are cleared.

NG → See step   5 

OK: Go to next step 

1. Turn the ignition switch off.
2. Clear the DTCs, refer to DTC CHECK / CLEAR .
3. Turn the ignition switch to ON (READY).
4. Drive the vehicle at a speed of 10 km/h (6 mph) or more for at least 60 seconds.
5. Check if the same DTC is recorded, refer to DTC CHECK / CLEAR .

   Result

   Result	Proceed to
   DTCs (C1464/31 and C1465/32) are not output	A
   DTCs (C1464/31 and/or C1465/32) are output	B

   HINT: 

   If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next suspected area, refer to PROBLEM SYMPTOMS TABLE .

B → See step   8 

A → See step   10 

Fig 1: Identifying Clearance And Front Speed Sensor Installation Position

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Turn the ignition switch off.
2. Check the speed sensor installation.

   OK

   There is no clearance between the sensor and the front steering knuckle.

   The installation bolt is tightened properly, refer to INSTALLATION - Step 1 .

NG → See step   11 

OK: Go to next step 

1. Remove the front speed sensor, refer to REMOVAL .
2. Check the speed sensor tip.

   OK

   The sensor tip is free of scratches, oil, and foreign matter.

   NOTE:

   • If no damage to the speed sensor tip is found during this inspection, do not replace the speed sensor.
   • Check the speed sensor signal after cleaning or replacement, refer to TEST MODE PROCEDURE .

NG → CLEAN OR REPLACE FRONT SPEED SENSOR 

OK: Go to next step 

1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
   Fig 2: Identifying Skid Control ECU And Front Speed Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the A46 or A47 skid control ECU connector and the front speed sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   for RH 

   for LH 

   Tester Connection	Condition	Specified Condition
   A46-22 (FR+) - A29-2 (FR+)	Always	Below 1 Ω
   A46-22 (FR+) - Body ground	Always	10 kΩ or higher
   A46-23 (FR-) - A29-1 (FR-)	Always	Below 1 Ω
   A46-23 (FR-) - Body ground	Always	10 kΩ or higher

   Tester Connection	Condition	Specified Condition
   A47-31 (FL+) - A12-2 (FL+)	Always	Below 1 Ω
   A47-31 (FL+) - Body ground	Always	10 kΩ or higher
   A47-32 (FL-) - A12-1 (FL-)	Always	Below 1 Ω
   A47-32 (FL-) - Body ground	Always	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Skid Control ECU)
   *2	Front view of wire harness connector (to Front Speed Sensor)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Turn the ignition switch off.
   Fig 3: Identifying Skid Control ECU Connector Terminals Waveform Graph

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Reconnect the skid control ECU connectors and the front speed sensor connectors.
3. Connect an oscilloscope to the front speed sensor terminal of the skid control ECU and body ground.
4. Check the waveform output when the wheels are rotated.

   OK

   The same waveform is output from all the sensors and there is no noise or interference in the waveform.

   HINT: 

   • As the vehicle speed (wheel revolution speed) increases, the wavelength shortens.
   • When noise is identified in the waveform on the oscilloscope, the erratic signals are generated due to speed sensor rotor scratches, looseness or attached foreign matter.
   TEXT IN ILLUSTRATION
   
   

   *1	Component with harness connected (Skid Control ECU)
   *2	Normal Signal Waveform

   NOTE:

   Check the speed sensor signal after cleaning or replacement, refer to TEST MODE PROCEDURE .

   HINT: 

   If the front speed sensor rotor needs to be replaced, replace it together with the front drive outboard joint shaft assembly.

NG → CLEAN OR REPLACE FRONT SPEED SENSOR OR FRONT SPEED SENSOR ROTOR 

OK: Go to next step 

1. Turn the ignition switch off.
2. Clear the DTCs, refer to DTC CHECK / CLEAR .
3. Turn the ignition switch to ON (READY).
4. Drive the vehicle at a speed of 10 km/h (6 mph) or more for at least 60 seconds.
5. Check if the same DTC is recorded, refer to DTC CHECK / CLEAR .

   Result

   Result	Proceed to
   DTCs (C1464/31 and C1465/32) are not output	A
   DTCs (C1464/31 and/or C1465/32) are output	B

   HINT: 

   If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next suspected area, refer to PROBLEM SYMPTOMS TABLE .

B → See step   12 

A → See step   10