Vehicle Stability Control System (For ADVICS Made)
BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM (for ADVICS Made): C1235/35,C1236/36,C1238/38,C1239/39,C1275/75-C1278/78: Foreign Object is Attached on Tip of Front Speed Sensor RH
C1278/78 - Abnormal Change in Output Signal of Rear Speed Sensor LH (Test Mode DTC)
DESCRIPTION
The speed sensors detect wheel speed and transmit the signals to the ECU. These signals are used for control of the ABS control system. Each of the front and rear rotors have 48 serrations.
When the rotors rotate, the magnetic field generated by the permanent magnet in the speed sensor induces an 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.
DTCs C1275/75 to C1278/78 can be cleared when the speed sensor sends a vehicle speed signal or the Test Mode ends. DTCs from C1275/75 to C1278/78 are output only in the Test Mode.
HINT
* DTC C1235/35 is for the front speed sensor RH.
* DTC C1236/36 is for the front speed sensor LH.
* DTC C1238/38 is for the rear speed sensor RH.
* DTC C1239/39 is for the rear speed sensor LH.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
When replacing the brake actuator assembly, perform zero point calibration Programming and Relearning.
HINT
When C0200/31, C0205/32, C0210/33, or C0215/34 is output together with C1235/35, C1236/36, C1238/38, or C1239/39, inspect and repair the trouble areas indicated by C0200/31, C0205/32, C0210/33, or C0215/34 first.
PROCEDURE
1. CHECK SPEED SENSOR AND SPEED SENSOR ROTOR SERRATIONS
(a) Disconnect the skid control ECU connector.
(b) Connect the oscilloscope to each speed sensor terminal of the skid control ECU.
(c) Check that a waveform is output when the tires are rotated (by the sensor circuit).
OK:
The same waveform is output from all the 4 wheels and there is no noise or interference in the waveform.
(d) Check that the waveform does not change while jiggling a connector or a wire harness.
OK:
The waveform does not change.
HINT
* As the vehicle speed (wheel revolution speed) increases, a cycle of the waveform narrows and the output voltage becomes greater.
* When noise is identified in the waveform on the oscilloscope, the erratic signals are generated due to speed sensor rotor's scratches, looseness or foreign matter attached to it.
NG -- INSPECT SPEED SENSOR
OK -- Continue to next step.
2. RECONFIRM DTC
(a) Reconnect the skid control ECU connector.
(b) Clear the DTC Vehicle Stability Control System (for ADVICS Made).
(c) Start the engine.
(d) Drive the vehicle at the speed of 12 mph (20 km/h) or more for at least 60 seconds.
(e) Check if the same DTC is recorded Vehicle Stability Control System (for ADVICS Made).
Result:
B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- USE SIMULATION METHOD TO CHECK
3. INSPECT SPEED SENSOR
(a) Disconnect each speed sensor connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
RH
LH
Result:
C -- REPLACE SPEED SENSOR
B -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - SPEED SENSOR)
A -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)
(a) Disconnect the skid control sensor wire.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
RH
LH
NOTICE:
Check the speed sensor signal after replacement Test Mode Procedure.
NG -- REPLACE SKID CONTROL SENSOR WIRE
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - SPEED SENSOR)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:
RH
LH
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
6. RECONFIRM DTC
(a) Reconnect the skid control sensor wire.
(b) Reconnect the skid control ECU connector and the speed sensor connector.
(c) Clear the DTC Vehicle Stability Control System (for ADVICS Made).
(d) Start the engine.
(e) Drive the vehicle at the speed of 12 mph (20 km/h) or more for at least 60 seconds.
(f) Check if the same DTC is recorded Vehicle Stability Control System (for ADVICS Made).
Result:
C -- USE SIMULATION METHOD TO CHECK
B -- CHECK SPEED SENSOR ROTOR
A -- Continue to next step.
7. CHECK FRONT SPEED SENSOR TIP
(a) Turn the ignition switch off.
(b) Remove the front speed sensor Removal.
(c) Check the speed sensor tip.
OK:
No scratches or foreign matter on the sensor tip.
NOTICE:
Check the speed sensor signal after cleaning or replacement Test Mode Procedure.
NG -- CLEAN OR REPLACE FRONT SPEED SENSOR
OK -- Continue to next step.
8. CHECK SPEED SENSOR ROTOR
(a) Turn the ignition switch off.
(b) Remove each speed sensor rotor.
(c) Check the speed sensor rotor.
OK:
No scratches, missing teeth, or foreign matter on the rotors.
NOTICE:
Check the speed sensor signal after cleaning or replacement Test Mode Procedure.
NG -- CLEAN OR REPLACE SPEED SENSOR ROTOR
OK -- Continue to next step.
9. RECONFIRM DTC
(a) Install the front speed sensor and the speed sensor rotor.
(b) Clear the DTC Vehicle Stability Control System (for ADVICS Made).
(c) Start the engine.
(d) Drive the vehicle at the speed of 12 mph (20 km/h) or more for at least 60 seconds.
(e) Check if the same DTC is recorded Vehicle Stability Control System (for ADVICS Made).
Result:
B -- USE SIMULATION METHOD TO CHECK
A -- REPLACE BRAKE ACTUATOR ASSEMBLY