Anti-Lock Brake System (for Hatchback)
BRAKE CONTROL: ANTI-LOCK BRAKE SYSTEM (for Hatchback): C1407,C1408: Open or Short in Rear Speed Sensor RH Circuit
C1408 - Open or Short in Rear Speed Sensor LH Circuit
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.
HINT
* DTCs C1273 and C1274 are output only in the Test Mode.
* DTCs C1273 and C1274 can be deleted when the speed sensor sends a vehicle speed signal or the Test Mode ends.
* DTCs C1407 and C1273 are for the rear speed sensor RH.
* DTCs C1408 and C1274 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.
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 a DTC Check For Intermittent Problems.
ABS/VSC/TRC:
OK:
There are no momentary interruptions.
HINT
Perform the above inspection before removing the sensor and connector.
NG -- CHECK IF SKID CONTROL ECU AND REAR SPEED SENSOR CONNECTOR ARE SECURELY CONNECTED
OK -- Continue to next step.
2. RECONFIRM DTC
(a) Clear the DTC ABS (Antilock Brake System) (for Hatchback).
(b) Start the engine.
(c) Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.
(d) Check if the same DTC is recorded ABS (Antilock Brake System) (for Hatchback).
Result:
B -- REPLACE REAR AXLE HUB AND BEARING ASSEMBLY
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)
3. CHECK IF SKID CONTROL ECU AND REAR SPEED SENSOR CONNECTOR ARE SECURELY CONNECTED
(a) Check if the skid control ECU and the rear speed sensor connectors are securely connected.
NEXT -- Continue to next step.
4. RECONFIRM DTC
(a) Clear the DTC ABS (Antilock Brake System) (for Hatchback).
(b) Start the engine.
(c) Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.
(d) Check if the same DTC is recorded ABS (Antilock Brake System) (for Hatchback).
Result:
B -- END
A -- Continue to next step.
5. INSPECT REAR SPEED SENSOR
(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors.
(b) Disconnect the rear speed sensor connector.
(c) 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.
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.
NG -- REPLACE REAR AXLE HUB AND BEARING ASSEMBLY (REAR SPEED SENSOR)
OK -- Continue to next step.
6. 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.
7. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR SPEED SENSOR)
(a) Reconnect the speed sensor wire.
(b) Disconnect the skid control ECU connector.
(c) Inspect both the connector case and the terminal for deformation and corrosion.
OK:
No deformation or corrosion.
(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.
8. 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
OK -- Continue to next step.
9. REPLACE REAR AXLE HUB AND BEARING ASSEMBLY
(a) Turn the ignition switch off.
(b) Replace the rear speed sensor and rear axle hub and bearing assembly 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 with rear speed sensor.
NOTICE:
Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
10. RECONFIRM DTC
(a) Clear the DTC ABS (Antilock Brake System) (for Hatchback).
(b) Start the engine.
(c) Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.
(d) Check if the same DTC is recorded ABS (Antilock Brake System) (for Hatchback).
Result:
HINT
If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step Problem Symptoms Table.
B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- END
11. CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Check For Intermittent Problems
12. END
13. REPLACE REAR AXLE HUB AND BEARING ASSEMBLY (REAR SPEED SENSOR) Removal
14. REPLACE SPEED SENSOR WIRE
15. REPAIR OR REPLACE HARNESS OR CONNECTOR
16. REPLACE BRAKE ACTUATOR ASSEMBLY Removal