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 C1464/31: Front Speed Sensor RH Circuit; 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	Front speed sensor RH open detection / Error or Normal	Error: Momentary interruption Normal: Normal	-
   FL Speed Open	Front speed sensor LH 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	Front speed sensor RH / Min.: 0 km/h (0 mph), Max.: 326.4 km/h (202 mph)	Vehicle stopped: 0 km/h (0 mph)	When driving at constant speed: No large fluctuations
   FL Wheel Speed	Front speed sensor LH / Min.: 0 km/h (0 mph), Max.: 326.4 km/h (202 mph)	Vehicle stopped: 0 km/h (0 mph)	When driving at constant speed: No large fluctuations

2. Check that 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 the reference chart. Refer to ON-VEHICLE INSPECTION .

   OK

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

NG → See step   5 

OK: Go to next step 

1. Turn the power 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 power switch off.
2. Clear the DTCs. Refer to DTC CHECK / CLEAR .
3. Turn the power switch on (READY).
4. Perform a road test.
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 step. Refer to PROBLEM SYMPTOMS TABLE .

B → See step   10 

A → See step   14 

1. Turn the power switch off.
   Fig 1: Identifying Front Speed Sensor

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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.

   Torque 

   8.5 N*m (87 kgf*cm, 75 in.*lbf)

NG → See step   16 

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:

   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 Connector And Front Speed Sensor Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the 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
   A58-18 (FR+) - A34-2 (FR+)	Always	Below 1 Ω
   A58-18 (FR+) - Body ground	Always	10 kΩ or higher
   A58-5 (FR-) - A34-1 (FR-)	Always	Below 1 Ω
   A58-5 (FR-) - Body ground	Always	10 kΩ or higher

   Tester Connection	Condition	Specified Condition
   A58-31 (FL+) - A15-2 (FL+)	Always	Below 1 Ω
   A58-31 (FL+) - Body ground	Always	10 kΩ or higher
   A58-32 (FL-) - A15-1 (FL-)	Always	Below 1 Ω
   A58-32 (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. Reconnect the skid control ECU connector.
   Fig 3: Identifying Skid Control ECU Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the power switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   for RH 

   for LH 

   Tester Connection	Switch Condition	Specified Condition
   A34-2 (FR+) - Body ground	Power switch on (IG)	5.7 to 14 V

   Tester Connection	Switch Condition	Specified Condition
   A15-2 (FL+) - Body ground	Power switch on (IG)	5.7 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Front Speed Sensor)

NG → See step   15 

OK: Go to next step 

1. Turn the power switch off.
2. Reconnect the front speed sensor connector.
3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
4. Turn the power switch on (READY).
5. Perform a road test.
6. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR .

   Result

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

   HINT: 

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

B → See step   14 

A: Go to next step 

1. Turn the power switch off.
2. Replace the front speed sensor. Refer to REMOVAL .
   NOTE:

   Check the speed sensor signal after replacement. Refer to TEST MODE PROCEDURE .

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Turn the power switch on (READY).
3. Perform a road test.
4. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR .

   Result

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

   HINT: 

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

B → END 

A: Go to next step 

1. Turn the power switch off.
2. Replace the front axle hub sub-assembly (front speed sensor rotor). Refer to REMOVAL .

   HINT: 

   The front speed sensor rotor is incorporated into the front axle hub sub-assembly.

   If the front speed sensor rotor needs to be replaced, replace it together with the front axle hub sub-assembly.

   NOTE:

   Check the speed sensor signal after replacement. Refer to TEST MODE PROCEDURE .

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Turn the power switch on (READY).
3. Perform a road test.
4. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR .

   Result

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

   HINT: 

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

B → END 

A → See step   15