Inspection Procedure

CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

Using a Techstream, check for any momentary interruption in the wire harness and connector corresponding to a DTC (See CHECK FOR INTERMITTENT PROBLEMS ).

ABS/VSC/TRAC:

MEASUREMENT ITEM NORMAL CONDITION CHART

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: Go to step 5

OK: Go to next step

READ VALUE USING TECHSTREAM (FRONT SPEED SENSOR)

Turn the ignition switch to OFF.
Connect the Techstream to the DLC3.
Start the engine.

Select the Data List mode on the Techstream (See DATA LIST / ACTIVE TEST ).

ABS/VSC/TRAC:

MEASUREMENT ITEM NORMAL CONDITION CHART

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

Check that there is no difference between the speed value output from the speed sensor displayed on the Techstream and the speed value displayed on the speedometer when driving the vehicle.
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 (See ON-VEHICLE INSPECTION ).

OK:

The speed value output from the speed sensor displayed on the Techstream is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).

NG: Go to step 7

OK: Go to next step

PERFORM TEST MODE (SIGNAL CHECK)
1. Perform sensor check in Test Mode procedure (See TEST MODE PROCEDURE ).
  OK:
  
  All Test Mode DTCs are erased.
NG: Go to step 7

OK: Go to next step

RECONFIRM DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Start the engine.
Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

Check if the same DTC is recorded (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC not output	A
DTC output	B

B: Go to step 12

A : CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (See CHECK FOR INTERMITTENT PROBLEMS )

CHECK IF SKID CONTROL ECU AND FRONT SPEED SENSOR CONNECTORS ARE SECURELY CONNECTED
1. Check if the skid control ECU and the front speed sensor connectors are securely connected.

RECONFIRM DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Start the engine.
Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

Check if the same DTC is recorded (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC output	A
DTC not output	B

B : END

A: Go to next step

CHECK FRONT SPEED SENSOR INSTALLATION
1. Turn the ignition switch to OFF.
2. Check the speed sensor installation.
  OK:
  
  There is no clearance between the sensor and the front steering knuckle. The installation nut is tightened properly.
  
  Torque:
  
  8.5 N*m (87 kgf*cm, 75 in.*lbf)
NG: INSTALL FRONT SPEED SENSOR CORRECTLY (See INSTALLATION )

Fig 1: Identifying Clearance Between Sensor And Front Steering Knuckle
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to next step
CHECK FRONT SPEED SENSOR TIP
1. Remove the front speed sensor (See REMOVAL ).
2. Check the speed sensor tip.
  OK:
  
  No scratches or foreign matter on the sensor tip.
  
  NOTE: Check the speed sensor signal after cleaning or replacement (See TEST MODE PROCEDURE ).
NG: CLEAN OR REPLACE FRONT SPEED SENSOR

OK: Go to next step

INSPECT FRONT SPEED SENSOR

Install the front speed sensor.
Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Disconnect the front speed sensor connector.

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

Standard resistance:

for RH

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
2 (FR+) - Body ground	Always	10 kΩ or higher
1 (FR-) - Body ground	Always	10 kΩ or higher

for LH

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
2 (FL+) - Body ground	Always	10 kΩ or higher
1 (FL-) - Body ground	Always	10 kΩ or higher

NOTE: Check the speed sensor signal after replacement (See TEST MODE PROCEDURE ).

NG: REPLACE FRONT SPEED SENSOR (See REMOVAL )

Fig 2: Measuring Resistance Between Front Speed Sensor Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to next step

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

Disconnect the skid control ECU connector.

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

Standard resistance:

for RH

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
A14-7 (FR+) - A5-2 (FR+)	Always	Below 1 Ω
A14-7 (FR+) - Body ground	Always	10 kΩ or higher
A14-6 (FR-) - A5-1 (FR-)	Always	Below 1 Ω
A14-6 (FR-) - Body ground	Always	10 kΩ or higher

for LH

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Condition	Specified Condition
A14-19 (FL+) - A9-2 (FL+)	Always	Below 1 Ω
A14-19 (FL+) - Body ground	Always	10 kΩ or higher
A14-18 (FL-) - A9-1 (FL-)	Always	Below 1 Ω
A14-18 (FL-) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 3: Identifying Skid Control ECU Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to next step

INSPECT SKID CONTROL ECU (SENSOR INPUT)

Reconnect the skid control ECU connector.
Turn the ignition switch to ON.

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

Standard voltage:

for RH

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
A5-2 (FR+) - Body ground	Ignition switch ON	8 to 14 V

for LH

TESTER CONNECTION SPECIFIED CONDITION CHART

Tester Connection	Switch Condition	Specified Condition
A9-2 (FL+) - Body ground	Ignition switch ON	8 to 14 V

NG: REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )

Fig 4: Identifying Skid Control ECU Connector Terminal

OK: Go to next step

REPLACE FRONT SPEED SENSOR
1. Turn the ignition switch to OFF.
2. Replace the front speed sensor (See REMOVAL ).
  NOTE: Check the speed sensor signal after cleaning or replacement (See TEST MODE PROCEDURE ).

RECONFIRM DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Start the engine.
Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

Check if the same DTC is recorded (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC output	A
DTC not output	B

B : END

A: Go to next step

REPLACE FRONT AXLE HUB BEARING
1. Turn the ignition switch to OFF.
2. Replace the front axle hub bearing (See REMOVAL ).
  HINT:
  
  The front speed sensor rotor is incorporated into the front axle hub bearing.
  
  CAUTION: Check the speed sensor signal after replacement (See TEST MODE PROCEDURE ).

RECONFIRM DTC

Clear the DTC (See DTC CHECK / CLEAR ).
Start the engine.
Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

Check if the same DTC is recorded (See DTC CHECK / CLEAR ).

Result

RESULT CHART

Result	Proceed to
DTC not output	A
DTC output	B

HINT:

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

B : REPLACE BRAKE ACTUATOR ASSEMBLY (See REMOVAL )

A : END