C1405
BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1405,C1406: Open or Short in Front Speed Sensor RH Circuit
C1406 - Open or Short in Front Speed Sensor LH Circuit
DESCRIPTION
The speed sensor detects the wheel speed and sends the appropriate signals to the skid control ECU. These signals are used for the ABS control system.
Speed sensor rotors have 48 serrations. The hall IC type speed sensor uses the frequency of output pulses to detect the vehicle speed. Because the sensor outputs digital pulses, it can detect vehicle speeds even when the vehicle is nearly stationary.
HINT
* DTC C1405 is for the front speed sensor RH.
* DTC C1406 is for the front speed sensor LH.
WIRING DIAGRAM
Refer to DTCs C1401 and C1402 C1401.
INSPECTION PROCEDURE
NOTICE:
When replacing the brake actuator assembly, perform zero point calibration Calibration.
PROCEDURE
1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)
(a) Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC Check for Intermittent Problems.
ABS/VSC/TRAC
ABS/VSC/TRAC:
OK:
There are no momentary interruptions.
HINT
Perform the above inspection before removing the sensor and connector.
NG -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)
OK -- Continue to next step.
2. READ VALUE USING TECHSTREAM (FRONT SPEED SENSOR)
(a) Turn the ignition switch off.
(b) Connect the Techstream to the DLC3.
(c) Start the engine.
(d) Select the Data List on the Techstream Data List / Active Test.
ABS/VSC/TRAC
ABS/VSC/TRAC:
(e) 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 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 -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)
OK -- Continue to next step.
3. RECONFIRM DTC
(a) Turn the ignition switch off.
(b) Clear the DTCs Vehicle Stability Control System.
(c) Start the engine.
(d) Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.
(e) Check if the same DTC is recorded Vehicle Stability Control System.
Result:
HINT
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.
B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Diagnosis System
4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)
(a) Turn the ignition switch off.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connectors.
(c) Disconnect the skid control ECU connector and the front speed sensor connector.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
for RH
for LH
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
5. INSPECT SKID CONTROL ECU (SENSOR INPUT)
(a) Reconnect the skid control ECU connector.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
for RH
for LH
NOTICE:
Check the speed sensor signal after replacement 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 Problem Symptoms Table.
NG -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
OK -- REPLACE FRONT SPEED SENSOR Removal