DTC C1721: Yaw Rate Sensor

WARNING: This page is about a different variant/trim than selected.

DTC Detecting condition:

A fault is detected if the sensor signal value is not correct.
A fault is detected if the steering angle sensor signal/lateral G sensor signal change while the yaw rate sensor signal indicates a constant value.
A fault is detected if the communication status of yaw rate sensor is abnormal.

Trouble symptom:

VDC does not operate.
Hill hold does not function.
EyeSight does not operate.

INTERVIEW CUSTOMERS .
Check if the vehicle ran the road with banks or sandy surface (which does not mean a dirt road).

Did the vehicle run the road with banks or sandy surface (which does not mean a dirt road)?

Yes: VDCCM and H/U may record DTC when the vehicle ran the road with banks or sandy surface (which does not mean a dirt road).

No: Go to 2.
CHECK INSTALLATION OF VDCCM AND H/U .
Is VDCCM and H/U installed properly without being tilted?

Is the bracket deformation-free?

Are the VDCCM and H/U installation bolts installed without missing or getting loose?

Yes: Go to 3.

No: Repair the defective part.
- Install VDCCM and H/U properly.
- Replace the bracket if faulty.
- Tighten the VDCCM and H/U installation bolt. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>GENERAL DESCRIPTION>COMPONENT>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM & H/U) . Go to 3.
CHECK OUTPUT OF YAW RATE AND G SENSOR WITH SUBARU SELECT MONITOR .
1. Drive the vehicle on a flat road.
2. Park the vehicle straight.
3. Using the Subaru Select Monitor, read data of [Yaw Rate Sensor] in the [Data Monitor] of [Brake Control]. Ref. to BRAKE CONTROL (DIAGNOSTICS) (HEV)>DATA MONITOR .
Is the value of [Yaw Rate Sensor] between -4 - 4 deg/s?

Yes: Go to 4.

No: Replace the VDCCM and H/U. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM & H/U) .
CHECK OUTPUT OF STEERING ANGLE SENSOR WITH SUBARU SELECT MONITOR .
1. Drive the vehicle on a flat road.
2. Park the vehicle straight.
3. Using the Subaru Select Monitor, read data of [Steering Angle Sensor] in the [Data Monitor] of [Brake Control]. Ref. to BRAKE CONTROL (DIAGNOSTICS) (HEV)>DATA MONITOR .
Is the value of [Steering Angle Sensor] between -10 - 10 deg?

Yes: Go to 5.

No: Perform the centering adjustment of steering wheel.
CHECK VDCCM AND H/U .
1. Turn the ignition switch to OFF.
2. Using the Subaru Select Monitor, perform the clear memory of [Brake Control]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
3. Execute the inspection mode. Ref. to BRAKE CONTROL (DIAGNOSTICS) (HEV)>INSPECTION MODE .
4. Read the DTC of [Brake Control] using the Subaru Select Monitor. Ref. to BRAKE CONTROL (DIAGNOSTICS) (HEV)>DIAGNOSTIC TROUBLE CODE (DTC) .
Is the same DTC displayed?

Yes: Replace the VDCCM and H/U. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM & H/U) .

No: Go to 6.
CHECK DETECTION OF OTHER DTCS FOR VDC .
Read the DTC of [Brake Control] using the Subaru Select Monitor. Ref. to BRAKE CONTROL (DIAGNOSTICS) (HEV)>DIAGNOSTIC TROUBLE CODE (DTC) .

Is any other DTC displayed?

Yes: Perform the diagnosis according to the DTC. Ref. to BRAKE CONTROL (DIAGNOSTICS) (HEV)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

No: Currently, it is normal. There may have been a temporary poor contact in the harness and connector or a temporary noise interference.