Foreign Object is Attached on Tip of Front Speed Sensor LH

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C0200/31: Right Front Wheel Speed Sensor Signal Malfunction

DTC C0200/31 - Right Front Wheel Speed Sensor Signal Malfunction

DTC C0205/32 - Left Front Wheel Speed Sensor Signal Malfunction

DTC C1235/35 - Foreign Object is Attached on Tip of Front Speed Sensor RH

DTC C1236/36 - Foreign Object is Attached on Tip of Front Speed Sensor LH

DESCRIPTION

The speed sensor detects wheel speed and sends the appropriate signals to the ECU. These signals are used for control of the vehicle stability control system. The front and rear rotors each have 48 serrations.
When the rotors rotate, the magnetic field emitted by the permanent magnet in the speed sensor generates AC voltage. Since the frequency of this AC voltage changes in direct proportion to the speed of the rotor, the frequency is used by the ECU to detect the speed of each wheel.

HINT:
- DTC C0200/31 and C1235/35 are for the front speed sensor RH.
- DTC C0205/32 and C1236/36 are for the front speed sensor LH.

WIRING DIAGRAM

INSPECTION PROCEDURE
HINT: When using the Techstream, start from*1. When not using the Techstream, start from*2.

PROCEDURE

1. READ VALUE USING TECHSTREAM (FRONT SPEED SENSOR)*1
(a) Check the Data List for proper functioning of the front speed sensor.

ABS/VSC/TRAC

OK:
There is almost no difference in displayed speed value.
HINT: There is tolerance of +/-10% in the speedometer indication.

OK -- INSPECT FRONT SPEED SENSOR (INSTALLATION)
NG -- Continue to next step.
2. INSPECT FRONT SPEED SENSOR*2

(a) Disconnect the A4 and A5 sensor connectors.
(b) Measure the resistance of the sensors.
Standard resistance:

HINT: Check the speed sensor signal after the speed sensor replacement Test Mode Procedure.

NG -- REPLACE FRONT SPEED SENSOR
OK -- Continue to next step.
3. CHECK WIRE HARNESS (SKID CONTROL ECU - FRONT SPEED SENSOR)

(a) Disconnect the S8 ECU connector.
(b) Measure the resistance of the wire harness side connectors.
Standard resistance:
LH

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.
4. INSPECT SPEED SENSOR AND SENSOR ROTOR SERRATIONS

(a) Connect an oscilloscope to terminals 14 (FR+) and 13 (FR-), and 16 (FL+) and 15 (FL-) of the S8 skid control ECU connector.
(b) Drive the vehicle at about 30 km/h (19 mph), and check the signal waveform.
OK:
Waveform is output, as shown above.
HINT:
- As vehicle speed (wheel revolution speed) increases, the wavelength shortens and the fluctuation in the output voltage becomes greater.
- When noise is identified in the waveform on the oscilloscope, error signals are generated due to scratches, looseness or foreign matter on the speed sensor rotor.

OK -- REPLACE SKID CONTROL ECU
NG -- Continue to next step.
5. INSPECT FRONT SPEED SENSOR (INSTALLATION)

(a) Check the speed sensor installation.
OK:
Installation bolt is tightened properly.
Torque: 8.5 N*m (87 kgf*cm, 75 in.*lbf)
There is no clearance between sensor and front steering knuckle.
HINT: Check the speed sensor signal after the speed sensor replacement Test Mode Procedure.

NG -- REPLACE FRONT SPEED SENSOR
OK -- Continue to next step.
6. INSPECT SPEED SENSOR (TIP)
(a) Remove the front speed sensor.
(b) Check the sensor tip.
OK:
No scratches or foreign matter on sensor tip.
HINT: Check the speed sensor signal after the speed sensor cleaning or replacement Test Mode Procedure.

NG -- CLEAN OR REPAIR SPEED SENSOR
OK -- Continue to next step.
7. INSPECT SPEED SENSOR ROTOR

(a) Remove the front speed sensor rotor.
(b) Check the sensor rotor serrations.
OK:
No scratches, missing teeth or foreign matter on sensor rotor.
HINT:
- If foreign matter is attached, remove it, and check the output waveform after reassembly.
- Check the speed sensor signal after cleaning the speed sensor rotor Test Mode Procedure.

NG -- CLEAN OR REPAIR SPEED SENSOR ROTOR
OK -- REPLACE SKID CONTROL ECU