June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Torque Sensor
The Torque Sensor delivers the driver’s demand and force acting on the tires to the EPS Control
Module. This EPS uses a Flux Ring style sensor that detects torque acting on the torsion bar of
the Steering Rack input shaft. The sensor consists of a Magnet Ring, Flux Ring, Flux Collecting
Ring, and Flux Yoke.

9-16

9-17

Torque Sensor

Input Shaft Cross Section

Magnetic Ring
The Magnet Ring, containing alternating North and South poles, is fixed to the Torsion Bar. As
the Input Shaft rotates, resistance from the driver’s demand creates torsion deforming the shaft.
This deformation rotates the Magnet Ring and varies the North and South magnetic flux lines that
are detected in the Flux Ring.

N

S

N

S
N

S

S

N

N

S
S

9-18
Input Shaft

9-19
Magnet Ring

146

N

9-20
Magnet Ring Poles
June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Flux Rings
The Flux Rings detect the North and South magnetic fluctuations from the Magnet Rings movement.
The 2 rings are identified as the Main and Sub.

9-21
Magnet Ring and Flux Rings

Flux Collecting Rings
The Flux Collecting Rings transfer the North and South magnetic fluctuations from the Flux Rings
to the Flux Collecting Yoke.
Magnet Ring

Flux Ring

Flux Ring

9-22

9-23

Magnet Ring and Flux Rings (Artwork)

Flux Rings (Artwork)

147

June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Flux Collecting Yoke
The Flux Collecting Yokes transfer the North and South magnetic fluctuations from the Flux
Collecting Rings to the Hall IC of the Torque Sensor. Based on the Torque Sensors interpretations,
motor direction and torque will be varied.
Flux Collecting
Rings

Magnet Ring

Flux Rings
9-24
Flux Rings and Flux Collecting Rings

9-25

9-26

Flux Collecting Rings

Flux Collecting Rings

148

June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Flux Collecting Yoke
The Flux Collecting Yokes transfer the North and South magnetic fluctuations from the Flux
Collecting Rings to the Hall IC of the Torque Sensor. Based on the Torque Sensors interpretations,
motor direction and torque will be varied.

Flux Collecting
Yoke

Hall IC

9-28

9-27
Flux Collecting Yoke and Hall IC

Flux Collecting Yoke and Hall IC

9-29
Sensor Removed

149

June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Alignment Collar
The Steering Gearbox shaft is now fitted with a plastic collar for alignment of the universal joint
during assembly.

9-31

9-30
Alignment Collar

Universal Joint Installation

NOTES:

150

June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Diagnostics
Since the Control Unit has been incorporated into the Gear Box assembly, diagnostics have been
simplified. Resolver and U, V, W Motor Winding related diagnostics are no longer necessary as
any faults relating to these components will require a Gear Box assembly replacement.

DTC

Item

None

Content of diagnosis

Without DTC

Normal

“Assist limitation” is displayed
in the current data «EPS
operating condition».

Assist limitation is performed
due to overheat protection
control.

“Overheating protection interThere are previous records of
vention history” in current
intervention to overheat prodata display shows 1 or
tection control.
more.

Inspect harness for
possible damage.
Replace if necessary. If
harness is OK, Torque
Sensor or control Unit
has failed. Replace the
Gear Box assembly.

Replacement of Gear Box
Assembly is necessary.

C2511

Torque Sensor Failure 1
(Main)

C2512

Torque Sensor Failure 2
(Sub)

C2513

Torque Sensor Failure 3
(Much Tolerance)

C2514

Torque Sensor Power Supply Failure

C2521

Motor Failure 1 (Motor)

C2522

Motor Malfunction 2
(Resolver)

C2531

ECU Failure 1 (CPU Failure)

Faulty main unit of power
steering control module

C2532

ECU Failure 2 (Peripheral
Circuit Failure)

Faulty main unit of power
steering control module

C2533

ECM Failure 3 (Board Temperature Sensor Failure)

Faulty main unit of power
steering control module

151

• Poor connector contact
• Forgot to connect connector
• Faulty torque sensor section circuit
• Faulty torque sensor coil

• Poor connector contact
• Forgot to connect connector
• Harness open/short circuit
• Motor open circuit
• Power transistor shorted/
open
• Terminal power supply or
ground short

June 2014

2015 Legacy and Outback
DTC

Conventional
CAN Diagnostics

New Technology Training
Item

(Module 926)

Content of diagnosis

C2541

Vehicle Speed Failure(Sensor Failure)

• Poor connector contact
• Forgot to connect connector
• Harness open/short circuit
• VDC system failure

C2543

Error Passive Status

Defective CAN communication

C2545

EyeSight System Abnormal

EyeSight system failure

C2546

EyeSight Value Abnormal

EyeSight system failure

C2547

EyeSight Check Sum Abnormal

• EyeSight system failure
• Defective CAN communication

C2548

Vehicle Dynamics Control
Module Abnormal

VDC system failure

C2551

Power Supply Relay Failure

• Power supply voltage malfunction
• Faulty relay contact

U0073

Control Module Communication Bus Off

Defective CAN communication

U0100

Lost Communication With
ECM/PCM “A”

Defective CAN communication

U0122

Lost Communication With
Vehicle Dynamics Control
Module

Defective CAN communication

U0126

Lost Communication With
Steering Angle Sensor Module

Defective CAN communication

U0155

Lost Communication With
Instrument Panel Cluster
(IPC) Control Module

Defective CAN communication

U0401

Invalid Data Received From
ECM/PCM “A”

Defective CAN communication

U0416

Invalid Data Received From
Vehicle Dynamics Control
Module

Defective CAN communication

U1235

Lost Communication With
EyeSight

Defective CAN communication

U1433

Invalid Data Received From
EyeSight

Defective CAN communication

152

June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

NOTES:

153

June 2014

2015 Legacy and Outback
Powertrain

New Technology Training

(Module 926)

FB 2.5
The 175-horsepower/ 174 lb-ft torque 4-cylinder FB 2.5 engine for the 2015 Legacy and Outback
emphasizes manageability in practical use with enhanced medium and low-speed torque. The
engine has been refined focusing on the air intake and exhaust systems. Engine quality has been
enhanced with measures against noise and vibration, weight reduction, and simplification. The
basic casting thickness of the cylinder block was decreased from 3.5 mm to 3.2 mm to reduce
weight while maintaining rigidity.

10-1
FB 2.5 Engine

Piston
The crown surface of the piston has been raised increasing compression from 10.0 to 10.3. The
center of gravity and skirt shape have been changed to reduce vibration. Sliding friction has
been reduced by the application of a new coating on the piston skirts. A new PVD (physical vapor
deposition) coating process is used for top compression and oil control rings to aid in abrasion
resistance. Piston ring tension has been decreased to reduce friction and improve fuel economy.
Note:

Engine oil and filter replacement for all 2015MY vehicles has been reduced to
6000 miles. The excessive oil consumption rate in the Owner’s Manual remains
at 1 quart every 1,200 miles. Always consult the latest Oil Consumption Test
procedures listed on Subarunet for updated information.
Optimized center
of gravity

Raised crown surface

Optimized skirt shape

10-2

Redesigned FB 2.5 Piston

154

June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Intake Cam Sprockets
The sensing surface for the intake cam position sensors has been changed to an inverted tooth
design. This is a similar design to the 2015 WRX FA 2.0.

2015MY

2014MY

INTAKE
Camshaft
Position
Sensor RH

INTAKE
Camshaft
Position
Sensor RH

ONE CAMSHAFT ROTATION

ONE CAMSHAFT ROTATION

10-3
Intake Cam Sprockets

Exhaust Cam Sprockets
Mass has been added to the LH Exhaust cam sprocket to reduce noise from the timing chain. The
RH Exhaust cam sprocket material was changed from stamped to sintered steel.

2014MY

2015MY

RH

LH

RH

LH
10-4

Exhaust Cam Sprockets

155

June 2014

2015 Legacy and Outback

New Technology Training

(Module 926)

Exhaust Cam Sprocket SST
New Special Tool 18334AA040 has been added to aid in the removal of the redesigned exhaust
cam sprockets. The new SST functions to extend the reach of existing SST 18334AA020.
ILLUSTRATION

TOOL NUMBER

DESCRIPTION

REMARKS

18355AA000

PULLEY WRENCH

• Used for removing and installing the crank pulley.
• Used for removing and installing cam sprocket.
• Used for rotating the intake cam sprocket LH.
• Used together with PULLEY WRENCH PIN
SET (18334AA000) or PULLEY WRENCH PIN
SET (18334AA020).
• Used with the PULLEY WRENCH PIN SET
(18334AA040) when removing and installing the
exhaust cam sprocket.

18334AA040
(Newly adopted
tool)