Foreign Object is Attached on Tip of Front Speed Sensor RH - Vehicle Stability Control System
BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: 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 the wheel speeds and send appropriate signals to the skid control ECU. Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change as the rotors turn.
The speed sensors detect those magnetic changes and send pulse signals to the skid control ECU. The ECU monitors the wheel speeds through these pulse signals to control the ABS control system.
When foreign matter or oil adheres to the speed sensor tip or speed sensor 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 can be deleted when the speed sensor sends a vehicle speed signal or the Test Mode ends. DTCs C1275/75 to C1278/78 are output only in the Test Mode.
HINT
When testing voltage, perform the test while the connector between the sensor and ECU is connected. Do not disconnect the connector between the sensor and ECU.
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:
* Disassembly of the rear speed sensor from the rear axle hub and bearing assembly is prohibited.
* When replacing the brake actuator assembly, perform zero point calibration Programming and Relearning.
HINT
When C0200/31, C0205/32, C0210/33 and/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 and/or C0215/34 first C0200 for front, or C1274 for rear).
PROCEDURE
1. INSPECT EACH SPEED SENSOR
(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors.
(b) Disconnect each speed sensor connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
for RH
for LH
Result:
NOTICE:
Check the speed sensor signal after replacement Test Mode Procedure.
HINT
Because the rear axle hub and bearing assembly cannot be disassembled. if the rear speed sensor needs replacement, replace the rear axle hub and bearing assembly.
B -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - EACH SPEED SENSOR)
C -- REPLACE EACH FRONT SPEED SENSOR OR REAR AXLE HUB AND BEARING ASSEMBLY
A -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (SPEED SENSOR WIRE)
(a) Disconnect the speed sensor wire.
(b) 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 SPEED SENSOR WIRE
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - EACH SPEED SENSOR)
(a) Reconnect the speed sensor wire.
(b) Disconnect the skid control ECU connector.
(c) 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.
4. 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
NG -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
OK -- Continue to next step.
5. RECONFIRM DTC
(a) Turn the ignition switch to OFF.
(b) Reconnect the speed sensor connector.
(c) Clear the DTC 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 -- REPLACE REAR AXLE HUB AND BEARING ASSEMBLY (REAR SPEED SENSOR AND REAR SPEED SENSOR ROTOR)
C -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Check for Intermittent Problems
A -- Continue to next step.
6. CHECK FRONT SPEED SENSOR TIP
(a) Turn the ignition switch to OFF.
(b) Remove the front speed sensor Removal.
(c) Check the speed sensor tip.
OK:
No scratches or foreign matter on the sensor tip.
HINT
If there is iron powder sticking to the rotor, this will result in a malfunction, so confirm that the rotor is not contaminated with foreign material before replacing the sensor.
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.
7. CHECK FRONT SPEED SENSOR ROTOR
(a) Remove front speed sensor rotor Removal.
(b) Check the front speed sensor rotors.
OK:
No scratches, oil, or foreign matter on the rotors.
NOTICE:
Check the speed sensor signal after cleaning or replacement Test Mode Procedure.
NG -- CLEAN OR REPLACE FRONT SPEED SENSOR ROTOR
OK -- Continue to next step.
8. REPLACE FRONT SPEED SENSOR
(a) Turn the ignition switch to OFF.
(b) Replace front speed sensor Removal.
NOTICE:
Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
9. RECONFIRM DTC
(a) Clear the DTC 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.
10. REPLACE FRONT SPEED SENSOR ROTOR
(a) Turn the ignition switch to OFF.
(b) Replace the front speed sensor rotor Removal.
HINT
The front speed sensor rotor is incorporated into the front axle hub sub-assembly.
NOTICE:
Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
11. RECONFIRM DTC
(a) Clear the DTC 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 BRAKE ACTUATOR ASSEMBLY Removal
12. REPLACE REAR AXLE HUB AND BEARING ASSEMBLY (REAR SPEED SENSOR AND REAR SPEED SENSOR ROTOR)
(a) Turn the ignition switch to OFF.
(b) Replace the rear axle hub and bearing assembly Removal.
HINT
The rear speed sensor rotor is incorporated into the rear axle hub and bearing assembly.
Because the rear axle hub and bearing assembly cannot be disassembled. if the rear speed sensor needs replacement, replace the rear axle hub and bearing assembly.
NOTICE:
Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
13. RECONFIRM DTC
(a) Clear the DTC 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 -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
A -- END