Toyota Yaris: Vehicle Stability Control System / Left Front Wheel Speed Sensor Circuit Intermittent (C05001F)

DESCRIPTION

The speed sensor detects wheel speed and sends the appropriate signals to the skid control ECU (brake actuator assembly). These signals are used for brake control.

Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change when the rotors turn.

Each speed sensor detects that magnetic change and sends a pulse signal to the skid control ECU (brake actuator assembly).

HINT:

When the connectors between the speed sensor and skid control ECU (brake actuator assembly) are connected, the following waveform is output.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

(a) Operate the GTS to check the Data List.

(b) Select the line graph display.

(c) Check for any momentary interruption in the wire harness and connector.

Click here

OK:

Normal (There are no momentary interruptions.)

NOTICE:

Perform the above inspection before removing the sensor and connector.

NG

GO TO STEP 5

OK

(a) Operate the GTS to check the Data List.

(b) Drive the vehicle and perform a road test.

(c) Check the speed value output from the speed sensor displayed on the GTS.

HINT:

Factors that affect the indicated vehicle speed include tire size, tire pressure, 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 GTS is similar to the speed indicated on the speedometer.

NG

GO TO STEP 5

OK

(a) Operate the GTS to clear the codes.

(b) Press the DTC clear button.

(c) Turn the ignition switch off.

NEXT

(a) Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.

(b) Operate the GTS to read the DTCs.

(c) Check if the same DTC is output.

A

USE SIMULATION METHOD TO CHECK

B

REPLACE BRAKE ACTUATOR ASSEMBLY

(a) Turn the ignition switch off.

*1 Front Speed Sensor LH *a Correct *b Incorrect *c 8.5 Nm *d No clearance

(b) Check the front speed sensor LH installation.

OK:

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

The installation bolt is tightened properly.

Torque

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

NG

REINSTALL OR REPLACE FRONT SPEED SENSOR LH

OK

(a) Remove the front speed sensor LH and the component with the front speed sensor rotor LH.

for front speed sensor LH: Click here

for front speed sensor rotor LH: Click here

(b) Check the front speed sensor LH tip and front speed sensor rotor LH.

OK:

No scratches, oil, or foreign matter on the front speed sensor LH tip and front speed sensor rotor LH.

NG

CLEAN OR REPLACE FRONT SPEED SENSOR LH OR COMPONENT WITH FRONT SPEED SENSOR ROTOR LH

OK

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

OK:

The connector is securely connected.

(b) Disconnect the A108 skid control ECU (brake actuator assembly) connector.

(c) Disconnect the A22 front speed sensor LH connector.

(d) Check both the connector case and the terminals for deformation and corrosion.

OK:

No deformation or corrosion.

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

Standard Resistance:

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

(a) Reconnect the A108 skid control ECU (brake actuator assembly) connector.

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

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

OK:

The connector is securely connected.

(c) Turn the ignition switch to ON.

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

Standard Voltage:

OK

REPLACE FRONT SPEED SENSOR LH

NG

REPLACE BRAKE ACTUATOR ASSEMBLY