C1275
BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1235/35: Foreign Object is Attached on Tip of Front Speed Sensor RH
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
DTC C1238/38 - Foreign Object is Attached on Tip of Rear Speed Sensor RH
DTC C1239/39 - Foreign Object is Attached on Tip of Rear Speed Sensor LH
DTC C1275/75 - Abnormal Change in Output Signal of Front Speed Sensor RH (Test Mode DTC)
DTC C1276/76 - Abnormal Change in Output Signal of Front Speed Sensor LH (Test Mode DTC)
DTC C1277/77 - Abnormal Change in Output Signal of Rear Speed Sensor RH (Test Mode DTC)
DTC C1278/78 - Abnormal Change in Output Signal of Rear Speed Sensor LH (Test Mode DTC)
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. This speed sensor contains a sensor IC, which consists of 2 MREs (Magnetic Resistance Elements). The speed sensor rotor, which consists of 48 sets of N and S poles arranged in a circle, is integrated with the inner race of the hub bearing.
To detect the rotation direction, the output waves are used to determine the relationship of the pulses that are generated by the 2 MREs. Upon receiving this signal, the sensor IC outputs a forward or backward waveform to the ECU.
When foreign matter adheres to the speed sensor tip or rotor these DTCs are output. An abnormal waveform input from the sensor determines these conditions.
These DTCs may be detected when a malfunction occurs in the connector terminals or wire harness of the speed sensor circuit.
DTCs C1275/75 to C1278/78 will be deleted when the speed sensor sends a wheel speed signal or when Test Mode ends. DTCs from C1275/75 to C1278/78 are output only in Test Mode.
HINT:
- DTCs C1235/35 and C1275/75 are for the front speed sensor RH.
- DTCs C1236/36 and C1276/76 are for the front speed sensor LH.
- DTCs C1238/38 and C1277/77 are for the rear speed sensor RH.
- DTCs C1239/39 and C1278/78 are for the rear speed sensor LH.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE: When replacing the skid control ECU, perform zero point calibration and store system information Testing and Inspection.
HINT: When C0200/31, C0205/32, C0210/33, and/or C0215/34 is output together with C1235/35, C1236/36, C1238/38, and/or C1239/39, inspect and repair the trouble areas indicated by C0200/31, C0205/32, C0210/33, and/or C0215/34 first C0200 for front, or C0210 for rear).
PROCEDURE
1. CHECK SPEED SENSOR AND SPEED SENSOR ROTOR SERRATIONS
(a) Connect the oscilloscope to each speed sensor terminal of the skid control ECU.
(b) Check waveform output when the wheel is rotated.
OK:
The same waveform is output from all the 4 wheels and there is no noise or interference in the waveform.
(c) 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 scratches, looseness or foreign matter attached to it.
Result:
C -- CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)
B -- CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)
A -- Continue to next step.
2. RECONFIRM DTC
(a) Turn the engine switch off.
(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(c) Start the engine.
(d) Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.
(e) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- REPLACE SKID CONTROL ECU
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)
3. CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)
(a) Turn the engine 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 sensor wire.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
for RH
for LH
NOTICE: Check the speed sensor signal after replacement Test Mode Procedure.
NG -- REPLACE SKID CONTROL SENSOR WIRE
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - FRONT SPEED SENSOR)
(a) Reconnect the skid control sensor wire.
(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. RECONFIRM DTC
(a) Reconnect the skid control ECU connector and the front speed sensor connector.
(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(c) Start the engine.
(d) Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.
(e) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)
A -- Continue to next step.
6. REPLACE FRONT SPEED SENSOR AND FRONT SPEED SENSOR ROTOR
(a) Turn the engine switch off.
(b) Replace the front speed sensor Removal.
(c) Replace the front axle hub sub-assembly (front speed sensor rotor) Removal.
HINT: The front speed sensor rotor is incorporated into the front axle hub sub-assembly.
If the front speed sensor rotor needs to be replaced, replace it together with the front axle hub sub-assembly with front speed sensor.
NOTICE: Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
7. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Start the engine.
(c) Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.
(d) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- END
A -- REPLACE SKID CONTROL ECU
8. CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)
(a) Turn the engine 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 sensor wire.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
for RH
for LH
NOTICE: Check the speed sensor signal after replacement Test Mode Procedure.
NG -- REPLACE SKID CONTROL SENSOR WIRE
OK -- Continue to next step.
9. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR SPEED SENSOR)
(a) Reconnect the skid control sensor wire.
(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 rear 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.
10. CHECK REAR SPEED SENSOR TIP
(a) Remove the rear speed sensor Removal.
(b) Check the speed sensor tip.
OK:
No scratches, oil, or foreign matter on the sensor tip.
NOTICE: Check the speed sensor signal after cleaning or replacement Test Mode Procedure.
NG -- CLEAN OR REPLACE REAR SPEED SENSOR
OK -- Continue to next step.
11. CHECK REAR SPEED SENSOR ROTOR
(a) Remove the rear speed sensor rotor Removal.
(b) Check the speed sensor rotor.
OK:
No scratches, oil, or foreign matter on the rotors.
NOTICE: Check the speed sensor signal after cleaning or replacement Test Mode Procedure.
HINT: The rear speed sensor rotor is incorporated into the rear axle hub and bearing assembly.
If the rear speed sensor rotor needs to be replaced, replace it together with the rear axle hub and bearing assembly.
NG -- CLEAN OR REPLACE REAR SPEED SENSOR ROTOR
OK -- Continue to next step.
12. RECONFIRM DTC
(a) Reconnect the skid control ECU connector and the rear speed sensor connector.
(b) Install the rear speed sensor and the rear speed sensor rotor.
(c) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(d) Start the engine.
(e) Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.
(f) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)
A -- Continue to next step.
13. REPLACE REAR SPEED SENSOR
(a) Turn the engine switch off.
(b) Replace the rear speed sensor Removal.
NOTICE: Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
14. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Start the engine.
(c) Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.
(d) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- END
A -- Continue to next step.
15. REPLACE REAR SPEED SENSOR ROTOR
(a) Turn the engine switch off.
(b) Replace the rear axle hub and bearing assembly (rear speed sensor rotor) Removal.
HINT: The rear speed sensor rotor is incorporated into the rear axle hub and bearing assembly.
If the rear speed sensor rotor needs to be replaced, replace it together with the rear axle hub and bearing assembly.
NOTICE: Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
16. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Start the engine.
(c) Drive the vehicle at a speed of 20 km/h (12 mph) or more for at least 60 seconds.
(d) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- END
A -- REPLACE SKID CONTROL ECU