POWER STEERING (DIAGNOSTICS)
PS(diag)
  1. Basic Diagnostic Procedure
  2. Check List for Interview
  3. General Description
  4. Electrical Component Location
  5. Control Module I/O Signal
  6. Inspection Mode
  7. Warning Light Illumination Pattern
  8. Diagnostic Procedure for Subaru Select Monitor Communication
  9. Data Monitor
  10. Freeze Frame Data
  11. Diagnostic Trouble Code (DTC)
  12. Diagnostic Procedure with Diagnostic Trouble Code (DTC)
POWER STEERING (DIAGNOSTICS) > Basic Diagnostic Procedure　
PROCEDURE

 

  • The power steering control module continues to operate after the engine stops and calculate the temperature in the control module. Therefore, before starting service of the power steering system which requires disconnection of the connector, stop the engine and allow approx. 30 minutes until the control module becomes cold.

  • Before removal or installation, be sure to remove any foreign matter (dust, moisture, oil, etc.) from the power steering control module connector.

  • Be sure to record the malfunction information obtained via DTC check.

  • Do not perform the clear memory until the repair or replacement of faulty parts is completed.

  • If a problem (connector terminal with foreign matter, etc.) is found, record the faulty part (take a photo • store the foreign matter, etc.).

1. PERFORM CUSTOMER INTERVIEW.

Ask the customer when and how the trouble occurred using the interview check list. POWER STEERING (DIAGNOSTICS)>Check List for Interview

Did you interview the customer?

2

Perform the interview, and 2

2. BASIC INSPECTION.

Perform basic inspection. POWER STEERING (DIAGNOSTICS)>General Description>INSPECTION

Is the check result OK?

3

Repair the faulty part found in basic inspection, and 3

3. CHECK WARNING LIGHT.

Check the lighting condition of STEERING warning light in the combination meter.

Does the STEERING warning light illuminate?

4

Currently, it is normal.

4. CHECK SUBARU SELECT MONITOR COMMUNICATION.
1.

Turn the ignition switch to OFF.

2.

Connect the Subaru Select Monitor to data link connector. COMMON(diag)>Data Link Connector

3.

Turn the ignition switch to ON and run the Subaru Select Monitor.

4.

Select [Power Steering System].

 

For detailed operation procedures, refer to “Help” of application.

Is communication possible?

5

Check the communication circuit. POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure for Subaru Select Monitor Communication

5. CHECK DTC.

Read the DTC of [Power Steering System] using the Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are DTC, time stamp and freeze frame data displayed?

Record the DTC, time stamp and freeze frame data. 7

6

6. PERFORM GENERAL DIAGNOSTICS.
1.

Execute the inspection mode. POWER STEERING (DIAGNOSTICS)>Inspection Mode

2.

Read the DTC of [Power Steering] using the Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

3.

Check that the DTC is not displayed.

Does the STEERING warning light illuminate at ignition switch ON, and turn off two seconds after the engine is started?

Finish the diagnosis.

POWER STEERING (DIAGNOSTICS)>Warning Light Illumination Pattern>STEERING WARNING LIGHT DOES NOT GO OFF

7. PERFORM DIAGNOSIS.
1.

Perform the diagnosis for the displayed DTCs. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2.

Repair or replace the cause of trouble.

3.

Execute the inspection mode. POWER STEERING (DIAGNOSTICS)>Inspection Mode

4.

Read the DTC of [Power Steering] using the Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC displayed in current malfunction?

Repeat step 7 until DTC is not shown.

Clear the memory to finish the diagnosis. COMMON(diag)>Clear memory

POWER STEERING (DIAGNOSTICS) > Check List for Interview　
CHECK

Check the following items regarding condition of the vehicle.

1. TROUBLE STATUS

Phenomenon of the vehicle

Steering is heavy

Steering is not smooth

Steering is unstable (wondering)

Steering does not return to center

Steering is not straight

Steering force required is not the same for right and left turn

Steering force required is not even

Steering is too light

Noise

Vibration

STEERING warning light illuminates

Other

Frequency

Always

Sometimes

Immediately after starting the engine

Only once

Other

Recovers after leaving it for     minutes

Steering wheel operation

Dry steering

When turning

Quick steering

Slow steering

Returning the steering wheel

End abutting

Releasing the steering wheel

Only supporting the steering wheel by hand

Repetitive dry steering

Beginning of steering

Steering wheel status / direction

Around center position

Near end of lock to lock

When turning the steering to right

When turning the steering to left

Both to right and to left

(1) Steering angle:     degrees

(2) Maneuvering time:     minutes

Slow steering

Quick steering

While holding the steering

When repeating the dry wheel operation

Vehicle speed

Stall 0 km/h (0 MPH)

Very low speed up to 20 km/h (up to 12 MPH)

Low speed up to 40 km/h (up to 25 MPH)

Medium speed up to 80 km/h (up to 50 MPH)

High speed 80 km/h or more (50 MPH or more)

At starting

While accelerating

While decelerating

When accelerating rapidly

When decelerating rapidly

Other

Engine speed

Idling

(1) Near     rpm

(2)   rpm —   rpm

(3)   rpm or more • or less
2. STATE OF STEERING WARNING LIGHT

STEERING warning light illuminates

Always

Sometimes

Only once

Does not illuminate

Other

Ignition key position

LOCK

ACC

ON (when starting engine)

START

ON (when starting engine, while engine is running)

ON (when starting engine, when engine is at a standstill)

Timing

Immediately after turning the ignition ON

Immediately after turning the ignition to START

At idling

During Auto Start Stop

When reversing

While accelerating

While decelerating

When cruising at    —   km/h (MPH)

When other electronic parts are in operation (part name:         operation condition:                 )
3. ENVIRONMENT

a) Weather

Fine

Cloudy

Rainy

Snowy

Other:

b) Outside temperature

   °C (°F)

c) Road

Inner city

Suburbs

Highway

Local street

Alley way

Private road

Parking lot

Mountain road

Paved road

Unpaved road

Gravel road

Sandy place

Muddy road

Concrete road

Stone pavement

Racetrack

Other:

d) Road surface

Dry

Wet

Covered with fresh snow

Covered with hardened snow

Other:

e) Tire

Tire chain

Studless tire

T-type tire (front RH, front LH, rear RH, rear LH)

f) Tire inflation pressure

Front RH:   kPa   Front LH:   kPa   Rear RH:   kPa   Rear LH:   kPa

g) Degree of wear

Front RH:   mm (in) Front LH:   mm (in) Rear RH:   mm (in) Rear LH:   mm (in)

h) Genuine part

Yes

No

Record after-market parts if any. (Steering wheel, audio, tires, and similar parts)

i) Condition of suspension alignment

j) Electrical load conditions

Audio

Air conditioner

Other

k) Loaded state

Condition:

l) Repair parts

No

Yes

Contents:

m) Others
POWER STEERING (DIAGNOSTICS) > General Description　
CAUTION
1. SRS AIRBAG SYSTEM
 

  • Do not use the electrical test equipment on the airbag system wiring harnesses and connector circuits.

  • Be careful not to damage the airbag system wiring harness.

POWER STEERING (DIAGNOSTICS) > General Description　
INSPECTION

Before performing diagnosis, check the following items which might be affecting the power steering problem.

1. BATTERY

Check the battery. STARTING/CHARGING SYSTEMS(H4DO)>Battery>INSPECTION 

2. TIRES

Check the tire specifications, tire wear and air pressure. WHEEL AND TIRE SYSTEM>General Description>SPECIFICATION

POWER STEERING (DIAGNOSTICS) > General Description　
PREPARATION TOOL
1. SPECIAL TOOL

ILLUSTRATION

TOOL NUMBER

DESCRIPTION

REMARKS

—

SUBARU SELECT MONITOR 4

Used for setting of each function and troubleshooting for electrical system.

 

For detailed operation procedures of Subaru Select Monitor 4, refer to “Help” of application.

34199AG100

SPECIAL TOOL HARNESS

Used for troubleshooting the electrical system.
2. GENERAL TOOL

TOOL NAME

REMARKS

Circuit tester

Used for measuring resistance, voltage and current.

Oscilloscope

Used for measuring the sensor.

DST-i

Used together with Subaru Select Monitor 4.
POWER STEERING (DIAGNOSTICS) > General Description　
SYSTEM BLOCK DIAGRAM
IGN PS-10126 WARNING INFORMATION TRANSMISSION STEERING SUPPORT INFORMATION TRANSMISSION ASSISTING DEVICE (MOTOR) OPERATION REQUEST TRANSMISSION IGN STATUS TRANSMISSION POWER SUPPLY VOLTAGE TRANSMISSION MOTOR OPERATION CURRENT TRANSMISSION MOTOR ROTATION ANGLE TRANSMISSION ENGINE SPEED TRANSMISSION VEHICLE SPEED TRANSMISSION STEERING ANGLE TRANSMISSION TORQUE TRANSMISSION MOTOR ROTATION ANGLE DETECTION ENGINE SPEED DETECTION ASSIST JUDGMENT STEERING SUPPORT FUNCTION WARNING FUNCTION POWER SUPPLY MOTOR OPERATION CURRENT DETECTION STEERING ANGLE DETECTION VEHICLE SPEED DETECTION TORQUE DETECTION ASSIST STOP/RESTART REQUEST TRANSMISSION AUTO START STOP PERMISSION/PROHIBITION INFORMATION TRANSMISSION AUTO START STOP COOPERATION FUNCTION
POWER STEERING (DIAGNOSTICS) > Electrical Component Location　
LOCATION

(1)

Steering gearbox (including power steering control module)

POWER STEERING (DIAGNOSTICS) > Control Module I/O Signal　
ELECTRICAL SPECIFICATION
B452 B450 PS-10105 1 2 3 4 5 6 7 8 9 10 1 2 TO TO

Connector No.

Terminal No.

Contents

Measuring condition

Standard

B450

1

Ignition power supply

Ignition SW: ON

Measurement between (B450) No. 1 — (B452) No. 1

9 — 16 V

B450

6

CAN communication

Digital signal; can not be measured

—

B450

7

CAN communication

Digital signal; can not be measured

—

B452

1

Ground

Always

Measurement between (B452) No. 1 — (B452) No. 2

10 — 16 V

B452

2

Battery power supply
POWER STEERING (DIAGNOSTICS) > Inspection Mode　
PROCEDURE
1.

Turn the ignition switch to OFF for 5 seconds or more.

2.

Start the engine.

3.

Idle the engine for five seconds or more.

4.

Operate the steering wheel from side to side.

5.

Reproduce the malfunction occurrence condition as much as possible.

POWER STEERING (DIAGNOSTICS) > Warning Light Illumination Pattern　
INSPECTION

(1)

STEERING warning light

POWER STEERING (DIAGNOSTICS) > Warning Light Illumination Pattern　
STEERING WARNING LIGHT DOES NOT COME ON
1. POWER STEERING ASSIST ENABLED

Detecting condition:

  • Defective combination meter

  • Defective harness

Trouble symptom:

When the ignition switch is turned to ON (engine OFF), the STEERING warning light does not illuminate.

 

It is operating normally if the warning light illuminates when the ignition switch is turned to ON (engine OFF), and turns off approximately two seconds after engine start.

1. CHECK ILLUMINATION OF OTHER LIGHTS.
no

Perform the instructed procedures.

yes
2. CHECK LAN SYSTEM.
no

Perform the instructed procedures.

yes
3. CHECK COMBINATION METER.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK ILLUMINATION OF OTHER LIGHTS.

Turn the ignition switch to ON. (Engine OFF)

Do other warning lights illuminate?

2

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>INSPECTION

2. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

3

Perform the diagnosis for LAN system.

3. CHECK COMBINATION METER.

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

Is the check result OK?

Current condition is normal.

Replace the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter

2. POWER STEERING ASSIST DISABLED

Detecting condition:

CAN communication error (engine rpm signal not received)

Trouble symptom:

  • Not assisted due to power supply voltage failure.

  • The STEERING warning light is normal but there is no power steering assist (steering feels heavy).

 

  • During driving, the assist system will not be activated when the ignition voltage drops.

  • Power steering assist is not started unless both of the ignition switch ON signal and the engine speed signal are input.

  • In any of the following cases, the power steering assist is limited and steering wheel operation may become heavy.

    If the steering wheel is held to an end for a long time, or the steering wheel turning to right and left at slow speed is repeated during parking, the assist limitation (overheat protection control) may operate to prevent failures by overheat.

    In this case, by stopping the engine for approx. 30 minutes for cooling, the assist will start operating. While assist limitation (overheat protection control) is in active, [Limited Assist] is displayed in [EPS Status] in the Subaru Select Monitor “Data Monitor”.

  • History can be confirmed on [ECU Overheat Protection] or [IG Count after ECU Overheat Protection(latest)] of “Data Monitor”.

  • The overheat protection control system is normal operation, therefore, the STEERING warning light will not come on and there will be no DTC displayed.

  • If the power steering system connector is disconnected while cooling under the overheat protection control, different DTC may be recorded. If there is no DTC and assist limitation is in active, stop the engine for approx. 10 minutes for cooling.

1. CHECK BATTERY.
no

Perform the instructed procedures.

yes
2. CHECK BATTERY TERMINAL AND FUSE.
no

Perform the instructed procedures.

yes
3. CHECK DTC.
yes

Perform the instructed procedures.

no
4. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
5. CHECK DATA MONITOR.
yes

Perform the instructed procedures.

no
6. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
7. CHECK DATA MONITOR.
no

Perform the instructed procedures.

yes
8. CHECK CONNECTOR.
yes

Perform the instructed procedures.

no

Perform the instructed procedures.

1. CHECK BATTERY.

Check the battery. STARTING/CHARGING SYSTEMS(H4DO)>Battery>INSPECTION

Is the check result OK?

2

Charge or replace the battery.

2. CHECK BATTERY TERMINAL AND FUSE.

Check the battery terminals and the fuse.

Is the check result OK?

3

Repair or replace faulty parts.

3. CHECK DTC.

Read the DTC of [Brake Control] using the Subaru Select Monitor. BRAKE CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC related to VDC system or ignition power supply system displayed?

Perform the diagnosis according to the DTC. BRAKE CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

4

4. CHECK DATA MONITOR.
1.

Start the engine.

2.

Using Subaru Select Monitor, select [Data Monitor] of [Power Steering] and display [Engine Speed]. POWER STEERING (DIAGNOSTICS)>Data Monitor

Is [Engine Speed] the same as that in the combination meter?

5

Check the CAN communication. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

5. CHECK DATA MONITOR.

Using Subaru Select Monitor, select [Data Monitor] of [Power Steering] and display [EPS Status]. POWER STEERING (DIAGNOSTICS)>Data Monitor

Is [Assist limitation] displayed?

It is possible that temporary assist limitation has occurred due to overheat protection. Stop the engine for approx. 30 minutes, and check again.

6

6. CHECK DATA MONITOR.
1.

Using Subaru Select Monitor, select [Data Monitor] of [Power Steering] and display [Torque Sensor Main] and [Torque Sensor Sub]. POWER STEERING (DIAGNOSTICS)>Data Monitor

2.

Move the steering wheel to the left and right.

Do the values of [Torque Sensor Main] and [Torque Sensor Sub] change along with the operation?

7

Check for poor contact of the torque sensor connector.

7. CHECK DATA MONITOR.

Using Subaru Select Monitor, select [Data Monitor] of [Power Steering] and display [IG voltage]. POWER STEERING (DIAGNOSTICS)>Data Monitor

Is [IG voltage] stable? (While wiggling the harness)

8

Check the ignition switch and IG voltage harness, and repair the defective part.

8. CHECK CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector (B204).

Are there any damages to terminal or other parts either on the power steering control module side or on the connector side?

Repair the terminal.

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Warning Light Illumination Pattern　
STEERING WARNING LIGHT DOES NOT GO OFF

Detecting condition:

  • Defective combination meter

  • Open circuit of harness

Trouble symptom:

When starting the engine, the STEERING warning light continues to illuminate.

1. CHECK DTC.

Read the DTC of [Power Steering] using the Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Are any DTCs displayed?

Perform the diagnosis according to the DTC. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

3

Perform the diagnosis for LAN system.

3. CHECK COMBINATION METER.

Check the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter System>OPERATION > SELF-DIAGNOSIS DISPLAY MODE

Is the check result OK?

Replace the steering box. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

Replace the combination meter. INSTRUMENTATION/DRIVER INFO>Combination Meter

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure for Subaru Select Monitor Communication　
INSPECTION

Detecting condition:

  • Defective harness connector

  • Defective power steering control module

Trouble symptom:

  • Communication is impossible between the power steering control module and Subaru Select Monitor.

  • After starting the engine, the STEERING warning light does not illuminate but steering effort is heavy.

Wiring diagram:

Electric power steering system WIRING SYSTEM>Electric Power Steering System

B452 A: B450 PS-10460 16 B: i288 3 4 B2 A1 14 6 8 B1 A7 A6 8 5 1 1 9 8 16 2 10 7 15 3 11 6 14 4 12 5 13 9 10 7 6 2 B203 B204 B205 B206 i288 B204 1 2 3 B206 1 2 B450 A: B452 B: 1 2 2 1 3 2 1 MB-16SBF-2(B) POWER STEERING CM DATA LINK CONNECTOR REF. TO CAN COMMUNICATION SYSTEM FB-60F/B FUSE NO. 10(IG) MB-17M/B FUSE NO. 11(B) FB-47F/B FUSE NO. 19(IG)

1. CHECK IGNITION SWITCH.

Is the ignition switch ON?

2

Turn the ignition switch to ON, and select the [Power Steering] using the Subaru Select Monitor.

2. CHECK BATTERY.
1.

Turn the ignition switch to OFF.

2.

Measure the battery voltage.

Is the voltage 11 V or more?

3

Charge or replace the battery.

3. CHECK BATTERY TERMINAL.

Is there poor contact at battery terminal?

Replace or tighten the battery terminal.

4

4. CHECK POWER STEERING CONTROL MODULE CONNECTOR INSTALLATION.

Turn the ignition switch to OFF.

Is the power steering control module connector inserted into the power steering control module until the clamp locks?

5

Insert the power steering control module connector into the power steering control module.

5. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

6

Perform the diagnosis for LAN system.

6. CHECK SUBARU SELECT MONITOR COMMUNICATION.
1.

Turn the ignition switch to ON.

2.

Check whether communication to electric power steering system can be executed normally.

Is the [Select Function] screen displayed?

Check DTC of electric power steering system. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

7

7. CHECK SUBARU SELECT MONITOR COMMUNICATION.

Connect the Subaru Select Monitor to another vehicle to check whether the communication for initializing can be executed normally.

Does the Subaru Select Monitor communicate normally?

8

Repair or replace the Subaru Select Monitor.

8. CHECK POWER SUPPLY CIRCUIT.
1.

Turn the ignition switch to ON. (Engine OFF)

2.

Measure the ignition power supply voltage between the power steering control module connector and chassis ground.

Connector & terminal

(B204) No. 3 (+) — Chassis ground (−):

(B206) No. 2 (+) — Chassis ground (−):

Is the voltage 10 — 15 V?

9

Repair the open circuit in the harness between the power steering control module and the battery.

9. CHECK HARNESS CONNECTOR BETWEEN POWER STEERING CONTROL MODULE AND CHASSIS GROUND.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector from the power steering control module.

3.

Measure the resistance of harness between power steering control module connector and chassis ground.

Connector & terminal

(B206) No. 1 — Chassis ground:

Is the resistance less than 10 Ω?

10

Repair the open circuit of the power steering control module ground circuit and the poor contact of connector.

10. CHECK POOR CONTACT OF CONNECTOR.

Is there poor contact of power steering control module power supply, ground circuit and data link connector?

Repair the connector.

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Data Monitor　
OPERATION
 
POWER STEERING (DIAGNOSTICS) > Data Monitor　
LIST

Item

Contents

Standard/Unit

Note

Power Supply Current

Primary current recognized by power steering CM

−128 — 127 A

—

Vehicle Speed

Vehicle speed

0 — 255 km/h

—

Engine Speed

Engine speed

0 — 12750 rpm

—

CU Sensing Current(q)

q axis current recognized by power steering CM

−128 — 127 A

—

Motor Current(U)

U axis current recognized by power steering CM

−128 — 127 A

—

Motor Current(V)

V axis current recognized by power steering CM

−128 — 127 A

—

Motor Speed

Motor rotational speed (rpm)

−4096 — 4064 rpm

—

CU Temperature

Power steering CM inner temperature

−50 — 205 °C

—

Power Supply Voltage

Voltage supplied to power steering CM

0 — 25.5V

—

Torque Sensor Power Supply

Voltage supplied to torque sensor

0 — 10.2V

—

IG Voltage

IGN voltage recognized by power steering CM

0 — 25.5V

—

CAN Bus Status

CAN bus status

Active/Passive/Bus off

—

EPS Status

EPS assist status

Normal/Assist stop/Assist limitation

—

CU Target current(q)

q axis indicator current from power steering CM to motor

−128 — 127 A

—

Assist Map

Assist MAP specification used for control

MAP1/MAP2/MAP3

—

ECU Overheat Protection

Number of interventions to the overheat protection control

0 — 250 Time

—

IG Count after ECU Overheat Protection(latest)

Number of times the ignition switch is ON at the last intervention to overheat protection control

0 — 65000 Time

—

IG Count after ECU Overheat Protection(Previous)

Number of times the ignition switch is ON at the second last intervention to overheat protection control

0 — 65000 Time

—

IG Count after ECU Overheat Protection(Before Previous)

Number of times the ignition switch is ON at the third last intervention to overheat protection control

0 — 65000 Time

—

Assist limited(Abnormal voltage)

Number of the intervention of assist restriction control due to voltage failure

0 — 250 Time

—

IGN-OFF Intervention Count while Running

Number of times the ignition switch is turned OFF while driving

0 — 250 Time

—

Torque Sensor Main

Torque sensor (main) output value

−15.36 — 15.24Nm

—

Torque Sensor Sub

Torque sensor (sub) output value

−15.36 — 15.24Nm

—

Steering Angle

Steering wheel rotational angle

−640 — 640 deg

—

POWER STEERING (DIAGNOSTICS) > Freeze Frame Data　
OPERATION
 
POWER STEERING (DIAGNOSTICS) > Freeze Frame Data　
LIST

Item

Contents

Standard/Unit

Note

Power Supply Current

Primary current recognized by power steering CM

−128 — 127 A

—

Vehicle Speed

Vehicle speed

0 — 255 km/h

—

Engine Speed

Engine speed

0 — 12750 rpm

—

CU Sensing Current(q)

q axis current recognized by power steering CM

−128 — 127 A

—

Motor Current(U)

U axis current recognized by power steering CM

−128 — 127 A

—

Motor Current(V)

V axis current recognized by power steering CM

−128 — 127 A

—

Motor Speed

Motor rotational speed (rpm)

−4096 — 4064 rpm

—

CU Temperature

Power steering CM inner temperature

−50 — 205 °C

—

Power Supply Voltage

Voltage supplied to power steering CM

0 — 25.5V

—

Torque Sensor Power Supply

Voltage supplied to torque sensor

0 — 10.2V

—

IG Voltage

IGN voltage recognized by power steering CM

0 — 25.5V

—

CAN Bus Status

CAN bus status

Active/Passive/Bus off

—

EPS Status

EPS assist status

Normal/Assist stop/Assist limitation

—

CU Target current(q)

q axis indicator current from power steering CM to motor

−128 — 127 A

—

Assist Map

Assist MAP specification used for control

MAP1/MAP2/MAP3

—

ECU Overheat Protection

Number of interventions to the overheat protection control

0 — 250 Time

—

IG Count after ECU Overheat Protection(latest)

Number of times the ignition switch is ON at the last intervention to overheat protection control

0 — 65000 Time

—

IG Count after ECU Overheat Protection(Previous)

Number of times the ignition switch is ON at the second last intervention to overheat protection control

0 — 65000 Time

—

IG Count after ECU Overheat Protection(Before Previous)

Number of times the ignition switch is ON at the third last intervention to overheat protection control

0 — 65000 Time

—

Assist limited(Abnormal voltage)

Number of the intervention of assist restriction control due to voltage failure

0 — 250 Time

—

IGN-OFF Intervention Count while Running

Number of times the ignition switch is turned OFF while driving

0 — 250 Time

—

Torque Sensor Main

Torque sensor (main) output value

−15.36 — 15.24 Nm

—

Torque Sensor Sub

Torque sensor (sub) output value

−15.36 — 15.24 Nm

—

Steering Angle

Steering wheel rotational angle

−640 — 640 deg

—

POWER STEERING (DIAGNOSTICS) > Diagnostic Trouble Code (DTC)　
OPERATION
 
POWER STEERING (DIAGNOSTICS) > Diagnostic Trouble Code (DTC)　
LIST

Code

Item

Reference

None

No display

POWER STEERING (DIAGNOSTICS)>Warning Light Illumination Pattern>STEERING WARNING LIGHT DOES NOT GO OFF

[Assist limitation] is displayed on the data monitor [EPS operating condition].

POWER STEERING (DIAGNOSTICS)>Warning Light Illumination Pattern>STEERING WARNING LIGHT DOES NOT GO OFF

The data monitor [Overheating protection intervention history] indicates at least 1 time.

POWER STEERING (DIAGNOSTICS)>Warning Light Illumination Pattern>STEERING WARNING LIGHT DOES NOT GO OFF

C2511

TORQUE SENSOR MAIN

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2511 TORQUE SENSOR MAIN

C2512

TORQUE SENSOR SUB

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2512 TORQUE SENSOR SUB

C2513

TORQUE SENSOR MUCH TOLERANCE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2513 TORQUE SENSOR MUCH TOLERANCE

C2514

TORQUE SENSOR POWER SUPPLY

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2514 TORQUE SENSOR POWER SUPPLY

C2521

MOTOR MALFUNCTION

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2521 MOTOR MALFUNCTION

C2522

RESOLVER SENSOR

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2522 RESOLVER SENSOR

C2531

CONTROL MODULE CPU

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2531 CONTROL MODULE CPU

C2532

CONTROL MODULE PERIPHERAL CIRCUIT

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2532 CONTROL MODULE PERIPHERAL CIRCUIT

C2533

CONTROL MODULE BOARD TEMPERATURE SENSOR

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2533 CONTROL MODULE BOARD TEMPERATURE SENSOR

C2541

VEHICLE DYNAMICS CONTROL MODULE VEHICLE SPEED SENSOR

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2541 VEHICLE DYNAMICS CONTROL MODULE VEHICLE SPEED SENSOR

C2543

ERROR PASSIVE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2543 ERROR PASSIVE

C2544

AUTO START STOP SYSTEM

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2544 AUTO START STOP SYSTEM

C2545

EYESIGHT SYSTEM

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2545 EYESIGHT SYSTEM

C2546

EYESIGHT VALUE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2546 EYESIGHT VALUE

C2547

EYESIGHT CHECK SUM

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2547 EYESIGHT CHECK SUM

C2551

POWER SUPPLY RELAY

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC C2551 POWER SUPPLY RELAY

U0073

CONTROL MODULE COMMUNICATION BUS OFF

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF

U0100

LOST COMMUNICATION WITH ECM/PCM "A"

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0100 LOST COMMUNICATION WITH ECM/PCM "A"

U0122

LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0122 LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE

U0126

LOST COMMUNICATION WITH STEERING ANGLE SENSOR MODULE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0126 LOST COMMUNICATION WITH STEERING ANGLE SENSOR MODULE

U0155

LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0155 LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE

U0401

INVALID DATA RECEIVED FROM ECM/PCM "A"

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0401 INVALID DATA RECEIVED FROM ECM/PCM "A"

U0416

INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U0416 INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE

U1120

LOST COMMUNICATION WITH AUTOSTART STOP CONTROL MODULE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U1120 LOST COMMUNICATION WITH AUTOSTART STOP CONTROL MODULE

U1235

LOST COMMUNICATION WITH EyeSight

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U1235 LOST COMMUNICATION WITH EyeSight

U1433

INVALID DATA RECEIVED FROM EyeSight

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U1433 INVALID DATA RECEIVED FROM EyeSight

U1469

INVALID DATA RECEIVED FROM AUTOSTART STOP CONTROL MODULE

POWER STEERING (DIAGNOSTICS)>Diagnostic Procedure with Diagnostic Trouble Code (DTC)>DTC U1469 INVALID DATA RECEIVED FROM AUTOSTART STOP CONTROL MODULE
POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2511 TORQUE SENSOR MAIN
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2512 TORQUE SENSOR SUB
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2513 TORQUE SENSOR MUCH TOLERANCE
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2514 TORQUE SENSOR POWER SUPPLY
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2521 MOTOR MALFUNCTION
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2522 RESOLVER SENSOR
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2531 CONTROL MODULE CPU
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2532 CONTROL MODULE PERIPHERAL CIRCUIT
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2533 CONTROL MODULE BOARD TEMPERATURE SENSOR
 

Do not perform the clear memory after checking DTCs.

 

When this code is displayed, replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2541 VEHICLE DYNAMICS CONTROL MODULE VEHICLE SPEED SENSOR

DTC detecting condition:

When VDCCM reception failure (related to vehicle speed sensor) is detected after the ignition switch is ON.

Trouble symptom:

The steering wheel operation feels heavy.

1. CHECK DTC.

Read the DTC of [Brake Control] using the Subaru Select Monitor. BRAKE CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is a DTC related to VDC system or vehicle speed signal system displayed?

Perform the diagnosis according to the DTC. BRAKE CONTROL (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

3

Perform the diagnosis for LAN system.

3. CHECK VEHICLE SPEED SIGNAL.
1.

Using Subaru Select Monitor, select [Data Monitor] of [Power Steering] and display [Vehicle Speed]. POWER STEERING (DIAGNOSTICS)>Data Monitor

2.

Lift up the vehicle (so that the wheels turn freely), start the engine, and raise engine speed in gear.

 

Be careful that no one is near the spinning tires and nothing gets caught in them.

3.

Check for whether the data changes according to vehicle speed.

Is the data in sync with the vehicle speed?

It is possible that temporary poor communication occurs. Clear the memory. COMMON(diag)>Clear memory

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2543 ERROR PASSIVE

DTC detecting condition:

When send/receive failure of CAN communication is detected after the ignition switch is ON.

Trouble symptom:

The steering wheel operation feels heavy.

Wiring diagram:

Electric power steering system WIRING SYSTEM>Electric Power Steering System

B452 A: B450 PS-10460 16 B: i288 3 4 B2 A1 14 6 8 B1 A7 A6 8 5 1 1 9 8 16 2 10 7 15 3 11 6 14 4 12 5 13 9 10 7 6 2 B203 B204 B205 B206 i288 B204 1 2 3 B206 1 2 B450 A: B452 B: 1 2 2 1 3 2 1 MB-16SBF-2(B) POWER STEERING CM DATA LINK CONNECTOR REF. TO CAN COMMUNICATION SYSTEM FB-60F/B FUSE NO. 10(IG) MB-17M/B FUSE NO. 11(B) FB-47F/B FUSE NO. 19(IG)

1. CHECK PERIPHERALS.

Check the data link connector.

Is any other electrical part connected to the data link connector or harness?

Disconnect the connection of electrical parts and perform inspection again.

2

2. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

3

Perform the diagnosis for LAN system.

3. CHECK DTC.

Read the DTC of [Power Steering] using the Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC C2543 displayed in current malfunction?

4

System is normal. Temporary interference from noise is a possible cause. Clear the memory to complete the diagnosis. COMMON(diag)>Clear memory

4. CHECK CONNECTOR.

Check the connecting condition of connector.

Is the connector firmly installed?

5

Install the connector, and check again.

5. CHECK CONNECTOR.
1.

Turn the ignition switch to OFF.

2.

Disconnect the connector (B204).

Is there crimped or spread portion in connector terminal on vehicle harness side and power steering control module side?

Repair or replace faulty parts.

6

6. CHECK HARNESS.

Check the harness related to CAN communication system.

Is there any fault in the harness?

Repair or replace the harness.

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2544 AUTO START STOP SYSTEM

DTC detecting condition:

  • When a failure of CAN communication is detected after the ignition switch is ON.

  • When the power steering control module has a detection error after the ignition switch is ON.

Trouble symptom:

Auto Start Stop does not operate.

1. CHECK DTC.

Read the DTC of [Auto Start Stop] using the Subaru Select Monitor. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC of Auto Start Stop system displayed?

Perform the diagnosis according to the DTC. AUTO START STOP (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

2

2. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

3

Perform the diagnosis for LAN system.

3. CHECK POWER STEERING CONTROL MODULE.
1.

Execute the inspection mode. POWER STEERING (DIAGNOSTICS)>Inspection Mode

2.

Read the DTC using Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC C2544 displayed in current malfunction?

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

It results from a temporary noise interference. Clear the memory to complete the diagnosis. COMMON(diag)>Clear memory

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2545 EYESIGHT SYSTEM

DTC detecting condition:

When the EyeSight system fail flag from stereo camera is received after the ignition switch is ON.

Trouble symptom:

EyeSight steering support function does not operate.

1. CHECK POOR CONTACT OF CONNECTOR.

Is there poor contact of the stereo camera connector?

Repair the poor contact of connector.

2

2. CHECK DTC.

Read the DTC of [EyeSight] using the Subaru Select Monitor. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC of EyeSight system displayed?

Perform the diagnosis according to the DTC. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

3

3. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

4

Perform the diagnosis for LAN system.

4. CHECK POWER STEERING CONTROL MODULE.
1.

Connect all connectors.

2.

Execute the inspection mode. POWER STEERING (DIAGNOSTICS)>Inspection Mode

3.

Read the DTC using Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC C2545 displayed in current malfunction?

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

It results from a temporary noise interference. Clear the memory to complete the diagnosis. COMMON(diag)>Clear memory

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2546 EYESIGHT VALUE

DTC detecting condition:

When the steering support indication value from stereo camera is out of range after the ignition switch is ON.

Trouble symptom:

EyeSight steering support function does not operate.

1. CHECK POOR CONTACT OF CONNECTOR.

Is there poor contact of the stereo camera connector?

Repair the poor contact of connector.

2

2. CHECK DTC.

Read the DTC of [EyeSight] using the Subaru Select Monitor. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC of EyeSight system displayed?

Perform the diagnosis according to the DTC. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

3

3. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

4

Perform the diagnosis for LAN system.

4. CHECK POWER STEERING CONTROL MODULE.
1.

Connect all connectors.

2.

Execute the inspection mode. POWER STEERING (DIAGNOSTICS)>Inspection Mode

3.

Read the DTC using Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC C2546 displayed in current malfunction?

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

It results from a temporary noise interference. Clear the memory to complete the diagnosis. COMMON(diag)>Clear memory

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2547 EYESIGHT CHECK SUM

DTC detecting condition:

When checksum error of EyeSight transmission data is detected after the ignition switch is ON.

Trouble symptom:

EyeSight steering support function does not operate.

1. CHECK POOR CONTACT OF CONNECTOR.

Is there poor contact of the stereo camera connector?

Repair the poor contact of connector.

2

2. CHECK DTC.

Read the DTC of [EyeSight] using the Subaru Select Monitor. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC of EyeSight system displayed?

Perform the diagnosis according to the DTC. EyeSight (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST

3

3. CHECK LAN SYSTEM.

Check the LAN system. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

Is the check result OK?

4

Perform the diagnosis for LAN system.

4. CHECK POWER STEERING CONTROL MODULE.
1.

Connect all connectors.

2.

Execute the inspection mode. POWER STEERING (DIAGNOSTICS)>Inspection Mode

3.

Read the DTC using Subaru Select Monitor. POWER STEERING (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)

Is DTC C2547 displayed in current malfunction?

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

It results from a temporary noise interference. Clear the memory to complete the diagnosis. COMMON(diag)>Clear memory

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC C2551 POWER SUPPLY RELAY

DTC detecting condition:

  • When short malfunction of power supply relay is detected at initial check.

  • When power supply voltage failure is detected after the ignition switch is ON.

  • When power supply voltage drop is detected with 500 rpm engine speed reception.

Trouble symptom:

  • The steering wheel operation feels heavy.

  • STEERING warning light illuminates.

Wiring diagram:

Electric power steering system WIRING SYSTEM>Electric Power Steering System

B452 A: B450 PS-10460 16 B: i288 3 4 B2 A1 14 6 8 B1 A7 A6 8 5 1 1 9 8 16 2 10 7 15 3 11 6 14 4 12 5 13 9 10 7 6 2 B203 B204 B205 B206 i288 B204 1 2 3 B206 1 2 B450 A: B452 B: 1 2 2 1 3 2 1 MB-16SBF-2(B) POWER STEERING CM DATA LINK CONNECTOR REF. TO CAN COMMUNICATION SYSTEM FB-60F/B FUSE NO. 10(IG) MB-17M/B FUSE NO. 11(B) FB-47F/B FUSE NO. 19(IG)
 

If power supply voltage failure exists at the vehicle side, the warning light goes off if the normal voltage returns.

1. CHECK BATTERY.

Check the battery. STARTING/CHARGING SYSTEMS(H4DO)>Battery>INSPECTION

Is the check result OK?

2

Charge or replace the battery.

2. CHECK BATTERY TERMINAL AND FUSE.

Check the battery terminals and the fuse.

Is the check result OK?

3

Repair or replace faulty parts.

3. CHECK WIRING HARNESS.
1.

Disconnect the connector. (B205, B206)

2.

Turn the ignition switch to ON.

3.

Using a tester and special tool harness, check the voltage between terminals.

Connector & terminal

(B205) No. 2 (+) — Chassis ground (−):

Is the voltage 12 V or more?

4

Repair the open circuit of harness or the poor contact of connector between the power steering control module and the battery.

4. CHECK GROUND CIRCUIT.
1.

Turn the ignition switch to OFF.

2.

Using a tester and special tool harness, check the resistance between terminals.

Connector & terminal

(B205) No. 1 — Chassis ground:

Is the resistance less than 1 Ω?

5

Repair the open circuit or poor contact of the harness between the power steering control module and chassis ground.

5. CHECK HARNESS.
1.

Turn the ignition switch to OFF.

2.

Disconnect the power steering control module connector (B452).

3.

Using a tester and special tool harness, check the resistance between harness terminals.

Connector & terminal

(B206) No. 1 — (B452) No. 1:

(B206) No. 2 — (B452) No. 2:

Is the resistance less than 1 Ω?

Replace the steering gearbox. POWER ASSISTED SYSTEM (POWER STEERING)>Electric Power Steering Gearbox

Repair or replace the harness.

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U0100 LOST COMMUNICATION WITH ECM/PCM "A"
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U0122 LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL MODULE
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U0126 LOST COMMUNICATION WITH STEERING ANGLE SENSOR MODULE
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U0155 LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER (IPC) CONTROL MODULE
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U0401 INVALID DATA RECEIVED FROM ECM/PCM "A"
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U0416 INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CONTROL MODULE
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U1120 LOST COMMUNICATION WITH AUTOSTART STOP CONTROL MODULE
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U1235 LOST COMMUNICATION WITH EyeSight
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U1433 INVALID DATA RECEIVED FROM EyeSight
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure

POWER STEERING (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)　
DTC U1469 INVALID DATA RECEIVED FROM AUTOSTART STOP CONTROL MODULE
 

Refer to “LAN SYSTEM (DIAGNOSTICS)” for diagnostic procedure. LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure