BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS ANTI-LOCK BRAKE SYSTEM C1405 Open or Short in Front Speed Sensor RH Circuit C1406 Open or Short in Front Speed Sensor LH Circuit

DESCRIPTION

Refer to DTCs C1413 and C1414.

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>C1271

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C1405	Open or Short in Front Speed Sensor RH Circuit	Either of the following is detected: 1. An open in the speed sensor signal circuit continues for 0.5 seconds or more. 2. With the IG1 terminal voltage 9.5 V or more, the sensor power supply voltage decreases for 0.5 seconds or more.	· Front speed sensor RH · Speed sensor circuit · Skid control ECU (brake actuator assembly)
C1406	Open or Short in Front Speed Sensor LH Circuit	Either of the following is detected: 1. An open in the speed sensor signal circuit continues for 0.5 seconds or more. 2. With the IG1 terminal voltage 9.5 V or more, the sensor power supply voltage decreases for 0.5 seconds or more.	· Front speed sensor LH · Speed sensor circuit · Skid control ECU (brake actuator assembly)

HINT:: Even after the trouble areas are repaired, the ABS warning light will not go off unless the following operations are performed:; 1.

Drive the vehicle at 20 km/h (12 mph) for 30 seconds or more and check that the ABS warning light goes off.

2.

Clear the DTCs.

HINT:: ·

DTC C1405 is for the front speed sensor RH.

·

DTC C1406 is for the front speed sensor LH.

WIRING DIAGRAM

Refer to DTCs C1413 and C1414.

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>C1271

PROCEDURE

1.CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

Using the GTS, check for any momentary interruption in the wire harness and connector corresponding to a DTC.

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>CHECK FOR INTERMITTENT PROBLEMS

Chassis > ABS/VSC/TRC > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
FR Speed Sensor Voltage Open	Front speed sensor RH voltage open detection	Error or Normal	Error: Momentary interruption Normal: Normal	-
FL Speed Sensor Voltage Open	Front speed sensor LH voltage open detection	Error or Normal	Error: Momentary interruption Normal: Normal	-

Chassis > ABS/VSC/TRC > Data List

Tester Display
FR Speed Sensor Voltage Open
FL Speed Sensor Voltage Open

50003 105 294,295

OK:: There are no momentary interruptions.

HINT:: Perform the above inspection before removing the sensor and connector.

Result:

Proceed to
OK
NG

2.READ VALUE USING GTS (FRONT SPEED SENSOR)

4.CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - FRONT SPEED SENSOR)

2.READ VALUE USING GTS (FRONT SPEED SENSOR)

Turn the ignition switch off.

Connect the GTS to the DLC3.

Start the engine.

Select the Data List using the GTS.

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>DATA LIST / ACTIVE TEST

Chassis > ABS/VSC/TRC > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
FR Wheel Speed	Front wheel speed sensor RH reading	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	Front wheel speed sensor LH reading	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

Chassis > ABS/VSC/TRC > Data List

Tester Display
FR Wheel Speed
FL Wheel Speed

50003 105 1,2

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 hereVehicle Interior>METER / GAUGE / DISPLAY>METER / GAUGE SYSTEM>ON-VEHICLE INSPECTION

OK:: The speed value output from the speed sensor displayed on the GTS is similar to the speed indicated on the speedometer.

Result:

Proceed to
OK
NG

3.RECONFIRM DTC

4.CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - FRONT SPEED SENSOR)

3.RECONFIRM DTC

Turn the ignition switch off.

Clear the DTCs.

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>DTC CHECK / CLEAR

Chassis > ABS/VSC/TRC > Clear DTCs: 50002 105

Turn the ignition switch off.

Start the engine.

Perform a road test.

Check if the same DTC is output.

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>DTC CHECK / CLEAR

Chassis > ABS/VSC/TRC > Trouble Codes: 50001 105

Result:

Result	Proceed to
DTCs C1405 and C1406 are not output.	A
DTCs C1405 and/or C1406 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 before replacing parts.; Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>PROBLEM SYMPTOMS TABLE

USE SIMULATION METHOD TO CHECK

Click hereGeneral>INTRODUCTION>HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS>HOW TO PROCEED WITH TROUBLESHOOTING

REPLACE BRAKE ACTUATOR ASSEMBLY

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>BRAKE ACTUATOR>REMOVAL

4.CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - FRONT SPEED SENSOR)

Turn the ignition switch off.

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

Disconnect the A48 skid control ECU (brake actuator assembly) connector.

Disconnect the A22 or A23 front speed sensor connector.

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

Standard Resistance:

for RH
Tester Connection	Condition	Specified Condition
A48-7 (FR+) - A22-2 (FR+)	Always	Below 1 Ω
A48-7 (FR+) or A22-2 (FR+) - Body ground	Always	10 kΩ or higher
A48-6 (FR-) - A22-1 (FR-)	Always	Below 1 Ω
A48-6 (FR-) or A22-1 (FR-) - Body ground	Always	10 kΩ or higher

for LH
Tester Connection	Condition	Specified Condition
A48-19 (FL+) - A23-2 (FL+)	Always	Below 1 Ω
A48-19 (FL+) or A23-2 (FL+) - Body ground	Always	10 kΩ or higher
A48-18 (FL-) - A23-1 (FL-)	Always	Below 1 Ω
A48-18 (FL-) or A23-1 (FL-) - Body ground	Always	10 kΩ or higher

Result:

Proceed to
OK
NG

5.INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR INPUT)

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR INPUT)

0.5,1.156 0.844,1.385 0.344,0.229 2.042,1.156 2.385,1.385 0.344,0.229 1.344,2.917 1.052,2.302 false 2.854,2.906 2.635,2.302 false 0.292,0.354 0.604,0.552 0.313,0.198 10 false *a 0.563,1.188 1.021,1.385 0.458,0.198 10 false A22 2.104,1.188 2.563,1.385 0.458,0.198 10 false A23 1.24,2.948 1.698,3.146 0.458,0.198 10 false FR+ 2.76,2.948 3.219,3.146 0.458,0.198 10 false FL+

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

Reconnect the A48 skid control ECU (brake actuator assembly) 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	Condition	Specified Condition
A22-2 (FR+) - Body ground	Ignition switch ON	5.7 to 14 V

for LH
Tester Connection	Condition	Specified Condition
A23-2 (FL+) - Body ground	Ignition switch ON	5.7 to 14 V

NOTICE:: Check the speed sensor signal after replacement.; Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>TEST MODE PROCEDURE

HINT:: If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.; Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>ANTI-LOCK BRAKE SYSTEM>PROBLEM SYMPTOMS TABLE

Result:

Proceed to
OK
NG

REPLACE FRONT SPEED SENSOR

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>FRONT SPEED SENSOR>REMOVAL

REPLACE BRAKE ACTUATOR ASSEMBLY

Click hereBrake>BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS>BRAKE ACTUATOR>REMOVAL