Subaru Crosstrek Service Manual: Dtc c0081 system failure

DTC detecting condition:

VDC long time sequential control

Trouble symptom:

• VDC does not operate.

• EyeSight does not operate.

1.CHECK INSTALLATION OF VDCCM&H/U.

Is VDCCM&H/U installed properly without being tilted?
Is the bracket deformation-free?
Are the VDCCM&H/U installation bolts installed without missing or getting loose?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 2.

Repair the defective part.

• Install VDCCM&H/U properly.

• Replace the bracket if faulty.

• Tighten the VDCCM&H/U installation bolt. General Description > COMPONENT">

2.CHECK STEERING WHEEL.

1) Drive the vehicle on a flat road.

2) Park the vehicle straight.

3) Check the steering wheel for deviation from center.

Is the deviation from the center of steering wheel less than 5°?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 3.

Perform the centering adjustment of steering wheel, and perform Set up mode for Neutral of Steering Angle Sensor & Lateral G Sensor 0 point. VDC Control Module and Hydraulic Control Unit (VDCCM&H/U) > ADJUSTMENT">
Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 3.

3.CHECK OUTPUT OF STEERING ANGLE SENSOR USING SUBARU SELECT MONITOR.

1) Adjust steering wheel to the center position.

2) Using the Subaru Select Monitor, select “Data monitor”. Subaru Select Monitor > OPERATION">

3) Read the «Steer Angle Sensor Op» displayed on display.

Is the reading of «Steer Angle Sensor Op» −10° — 10°?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 4.

Check the installation of the steering wheel and steering angle sensor, and correct the installation if it is improper. If the installation condition is correct, replace the sensor.

4.CHECK OUTPUT OF SENSORS USING SUBARU SELECT MONITOR.

1) Drive the vehicle on a flat road.

2) Park the vehicle straight.

3) Using the Subaru Select Monitor, select “Data monitor”. Subaru Select Monitor > OPERATION">

4) Read «Lateral G sensor Output», «Fr Rr G sensor Output», and «Yaw Rate Sensor Output» displayed on display.

Is the reading of each sensor following value?
«Lateral G sensor Output»: −2 — 2 m/s2
«Fr Rr G sensor Output»: −2 — 2 m/s2
«Yaw Rate Sensor Output»: −4 deg/s — 4 deg/s

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 5.

Recheck from step 1, and if the problem is not solved, Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 8.

5.SET 0 POINT FOR LONGITUDINAL G SENSOR USING SUBARU SELECT MONITOR.

1) Using the Subaru Select Monitor, select “Work Support”.

2) Perform the “Longitudinal G sensor & lateral G sensor 0 point setting mode”. VDC Control Module and Hydraulic Control Unit (VDCCM&H/U) > ADJUSTMENT">

Is the 0 point setting successful?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 6.

Recheck from step 1, and when the 0 point setting is not possible, replace the VDCCM&H/U and steering angle sensor. VDC Control Module and Hydraulic Control Unit (VDCCM&H/U)"> Steering Angle Sensor">

6.PERFORM DRIVING TEST.

Drive approximately 10 minutes, and check if the warning lights illuminate or improperly operate during driving.

Did the ABS warning light or VDC warning light remain off?
Does ABS or VDC operate without malfunction?

Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C0081 SYSTEM FAILURE">Go to Step 7.

Recheck from step 1, and when the warning lights illuminate or improperly operate, replace the VDCCM&H/U. VDC Control Module and Hydraulic Control Unit (VDCCM&H/U)">

7.CHECK OUTPUT OF SENSORS USING SUBARU SELECT MONITOR.

1) Park the vehicle on a level surface.

2) Using the Subaru Select Monitor, select “Data monitor”. Subaru Select Monitor > OPERATION">

3) Read «Lateral G sensor Output», «Fr Rr G sensor Output», and «Yaw Rate Sensor Output» displayed on display.

Is the reading of each sensor following value?
«Lateral G sensor Output»: −1.5 — 1.5 m/s2
«Fr Rr G sensor Output»: −1.5 — 1.5 m/s2
«Yaw Rate Sensor Output»: −4 deg/s — 4 deg/s

Currently, it is normal. There may have been a temporary poor contact in the harness and connector or a temporary noise interference.

Replace the VDCCM&H/U. VDC Control Module and Hydraulic Control Unit (VDCCM&H/U)">

8.CHECK OUTPUT OF SENSORS USING SUBARU SELECT MONITOR.

1) Remove the VDCCM&H/U installation bolt and bracket.

2) Keep VDCCM&H/U in a horizontal position.

3) Using the Subaru Select Monitor, select “Data monitor”. Subaru Select Monitor > OPERATION">

4) Read «Lateral G sensor Output», «Fr Rr G sensor Output», and «Yaw Rate Sensor Output» displayed on display.

When VDCCM&H/U is in a horizontal position, is the reading of each sensor following value?
«Lateral G sensor Output»: −1.5 — 1.5 m/s2
«Fr Rr G sensor Output»: −1.5 — 1.5 m/s2
«Yaw Rate Sensor Output»: −4 deg/s — 4 deg/s

Check the bracket and brake pipe, and install VDCCM&H/U in a horizontal position to the vehicle.

Replace the VDCCM&H/U. VDC Control Module and Hydraulic Control Unit (VDCCM&H/U)">

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