C1404

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1403, C1273, C1274, C1404: Rear Speed Sensor RH Malfunction
C1404 - Rear Speed Sensor LH Malfunction

DESCRIPTION

The speed sensor detects wheel speed and sends the appropriate signals to the skid control ECU. These signals are used for ABS control.

Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change when the rotors turn.

Each speed sensor detects that magnetic change and sends a pulse signal to the skid control ECU.

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
* DTC C1403 and C1273 are for the rear speed sensor RH.
* DTC C1404 and C1274 are for the rear speed sensor LH.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Disassembly of the speed sensor from the rear axle hub and bearing assembly is prohibited.

PROCEDURE

1. 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.

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.

Text in Illustration





NG -- REPLACE REAR AXLE HUB AND BEARING ASSEMBLY Removal
OK -- Continue to next step.

2. READ VALUE USING TECHSTREAM (REAR SPEED SENSOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.

(e) According to the display on the Techstream, read the Data List.

ABS/VSC/TRAC





(f) Check that there is no difference between the speed value output from the speed sensor displayed on the Techstream and the speed value displayed on the speedometer when driving the vehicle.

HINT
Factors that affect the indicated vehicle speed include tire size, tire inflation, 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 On-Vehicle Inspection.

OK:

The speed value output from the speed sensor displayed on the Techstream is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).

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.
* 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.

NG -- REPLACE REAR AXLE HUB AND BEARING ASSEMBLY Removal

OK -- END