C1273
BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1273, C1274, C1332, C1333, C1466, C1467; Low Output Signal of Rear Speed Sensor RH (Test Mode DTC); 2013 MY FR-S [03/2012 -]
C1273 - Low Output Signal of Rear Speed Sensor RH (Test Mode DTC)
C1274 - Low Output Signal of Rear Speed Sensor LH (Test Mode DTC)
C1332 - Open in Rear Speed Sensor RH
C1333 - Open in Rear Speed Sensor LH
C1466 - Rear Speed Sensor RH
C1467 - Rear Speed Sensor LH
DESCRIPTION
Each speed sensor detects the wheel speed and sends the appropriate signals to the skid control ECU (brake actuator assembly). These signals are used by the brake control system.
Speed sensor rotors have row of alternating N and S magnetic poles, and their magnetic fields change when the rotors turn.
Each speed sensor detects that magnetic field change and sends a pulse signal to the skid control ECU (brake actuator assembly).
DTCs C1273 and C1274 are cleared when the speed sensor sends a vehicle speed signal or when Test Mode ends. DTCs C1273 and C1274 are output only in Test Mode.
HINT
* DTCs C1273, C1332 and C1466 are for the rear speed sensor RH.
* DTCs C1274, C1333 and C1467 are for the rear speed sensor LH.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
When replacing the skid control ECU (brake actuator assembly), perform VSC sensor neutral memorization Programming and Relearning.
PROCEDURE
1. READ VALUE USING TECHSTREAM (REAR SPEED SENSOR)
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Select the Data List using the Techstream Data List / Active Test.
ABS/VSC/TRAC
(d) Check the speed value output from the speed sensor displayed on the Techstream.
HINT
Factors that affect the indicated vehicle speed include tire size, tire pressure, 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 Component Tests and General Diagnostics.
OK:
The speed value output from the speed sensor displayed on the Techstream is similar to the speed indicated on the speedometer.
NG -- CHECK REAR SPEED SENSOR INSTALLATION
OK -- Continue to next step.
2. PERFORM TEST MODE INSPECTION (SIGNAL CHECK)
(a) Turn the ignition switch off.
(b) Perform the sensor check using the Test Mode procedure Test Mode Procedure.
OK:
All Test Mode DTCs are not output.
NG -- CHECK REAR SPEED SENSOR INSTALLATION
OK -- Continue to next step.
3. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the ignition switch off.
(c) Start the engine.
(d) Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.
(e) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- REPLACE REAR SPEED SENSOR
A -- CHECK FOR INTERMITTENT PROBLEMS
4. CHECK REAR SPEED SENSOR INSTALLATION
(a) Turn the ignition switch off.
(b) Check the speed sensor installation.
OK:
There is no clearance between the sensor and the rear axle carrier sub-assembly.
The installation bolt is tightened properly.
Torque
7.5 N*m (76 kgf*cm, 66 in.*lbf)
NG -- INSTALL REAR SPEED SENSOR CORRECTLY Installation
OK -- Continue to next step.
5. CHECK REAR SPEED SENSOR TIP
(a) Remove the rear speed sensor Removal.
(b) 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 REAR SPEED SENSOR
OK -- Continue to next step.
6. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - REAR SPEED SENSOR)
(a) Install the rear speed sensor Installation.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connector.
(c) Disconnect the skid control ECU (brake actuator assembly) 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.
7. INSPECT BRAKE ACTUATOR ASSEMBLY (REAR SPEED SENSOR POWER SOURCE TERMINAL)
(a) Reconnect the skid control ECU (brake actuator assembly) connector.
(b) 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.
8. RECONFIRM DTC
(a) Reconnect the rear speed sensor connector.
(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(c) Turn the ignition switch off.
(d) Start the engine.
(e) Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.
(f) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- CHECK FOR INTERMITTENT PROBLEMS
A -- Continue to next step.
9. REPLACE REAR SPEED SENSOR
(a) Turn the ignition 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.
10. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the ignition switch off.
(c) Start the engine.
(d) Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.
(e) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- END
A -- Continue to next step.
11. REPLACE REAR SPEED SENSOR ROTOR
(a) Turn the ignition switch off.
(b) Replace the rear speed sensor rotor Removal.
HINT
If the rear speed sensor rotor needs to be replaced, replace the rear axle hub and bearing assembly.
NOTICE:
Check the speed sensor signal after replacement Test Mode Procedure.
NEXT -- Continue to next step.
12. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the ignition switch off.
(c) Start the engine.
(d) Drive the vehicle at a speed of 45 km/h (28 mph) or more for at least 120 seconds.
(e) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
HINT
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts Problem Symptoms Table.
B -- END
A -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal