Subaru BRZ 2013 · Service Manual Steering

Power steering system

Precautions Parts location System information Troubleshooting Diagnostic trouble codes Circuit diagnosis Removal / installation Other

POWER ASSISTED SYSTEM
POWER STEERING SYSTEM
PRECAUTIONS
1. Correct handling and precautions for operation
(1) Handling of electrical parts
(a) Do not apply any impact to any electrical parts such as the power steering computer ASSY. Be sure to replace with a new part if strong impact is applied (such as hitting or dropping the part).
(b) Do not expose electric parts to extreme temperatures or high humidity.
(c) Do not touch the connector terminals as they may become deformed, or damaged due to static electricity discharge.
(2) Handling of the power steering computer ASSY
(a) Be sure to use new replacement parts when replacing the power steering computer ASSY.
CAUTION:
Do not install any power steering computer ASSY that is designed to be used with other vehicles (such as demonstration models).
(b) Always perform a steering zero point calibration after replacing the power steering computer ASSY. (Refer to )
(3) Precautions when connecting or disconnecting connectors
(a) Before you disconnect any connectors related to the power steering system, turn the ignition to IG ON and set the steering to the straight-ahead position. Turn the ignition to IG OFF and disconnect the connector after disconnecting the battery ground terminal.
(b) Before you connect any connectors related to the power steering system, confirm that the ignition is turned to IG OFF, connect the connector and turn the ignition to IG ON while the steering is in the straight-ahead position.
CAUTION:
Do not turn the ignition to IG ON if the steering is not in the straight-ahead position.
(c) If the above procedures are not carried out, the steering neutral (zero point) position can shift and you may experience a difference in the steering effort required for the left and right directions. Please perform a zero point calibration if you notice any difference in the steering effort for the left and right directions. (Refer to )
2. Precautions for CAN communication
(1) CAN communication is used for sending and receiving information from each computer, sending warning signals to the combination meter ASSY, and communication with the DLC3. A communication error code is output if there is a problem with the CAN communication line.
(2) If a CAN communication error code is output, repair the malfunction causing the communication line error and perform power steering system troubleshooting under a normal data communication state.
(3) For precautions when repairing the CAN communication system, please refer to .
FUNCTION INSPECTION
1. Dry steering torque check
WARNING:
As this maintenance procedure may have an effect on the SRS airbag system, be sure to check the SRS airbag system precautions before commencing work. (Refer to )
(1) Park the vehicle on a level paved surface, and set the steering wheel to the straight-ahead position.
(2) Disconnect the battery ground terminal.
CAUTION:
After turning the ignition switch to OFF, you may have to wait for a while before disconnecting the battery terminals. Check appropriate precautions for battery terminal disconnection before proceeding. (Refer to )
(3) Remove the horn button ASSY. (Refer to )
(4) Connect the negative terminal of the battery.
(5) Check that the steering wheel set nut is not loose.

Standard value:
Tightening torque=39N·m { 398kgf·cm}
(6) Start the engine and place the vehicle in a state where the power steering can operate.
(7) Check the torque while turning the steering wheel a quarter turn to the right from the straight-ahead position.

Standard value:
Tightening torque=6.0N·m { 61kgf·cm}
or less
(8) Check the torque in the same manner while turning to the left.
(9) Set the steering wheel to the straight-ahead position.
(10) Disconnect the battery ground terminal.
CAUTION:
After turning the ignition switch to OFF, you may have to wait for a while before disconnecting the battery terminals. Check appropriate precautions for battery terminal disconnection before proceeding. (Refer to )
(11) Install the horn button ASSY. (Refer to )
(12) Connect the negative terminal of the battery.
PARTS LOCATION
LIST OF DIAGNOSTIC CODES
Power steering system
Diagnostic codes
 Diagnostic items
 Light on
 Normal return condition
 Reference pages
C1511
 [Torque sensor 1 abnormal]
 *1
 Once again, IG ON
  
C1512
 [Torque sensor 2 abnormal]
 *1
 Once again, IG ON
  
C1513
 [Torque sensor 3 abnormal]
 *1
 Once again, IG ON
  
C1514
 [Torque Sensor Power Supply Failure]
 *1
 Once again, IG ON
  
C1515
 [Torque Sensor Zero Point Adjustment Undone]
 *1
 Perform torque sensor zero point calibration
  
C1516
 [Torque Sensor Zero Point Adjustment Incomplete]
 *1
 Delete diagnosis code
  
C1517
 [Torque sensor hold abnormality]
 *1
 Once again, IG ON
  
C1521
 [Motor failure 1]
 *1
 Once again, IG ON
  
C1522
 [Motor failure 2]
 *1
 Once again, IG ON
  
C1523
 [Motor failure 3]
 *1
 Once again, IG ON
  
C1524
 [Motor failure 4]
 *1
 Once again, IG ON
  
C1525
 [Resolver not corrected]
 *1
 Perform rotation angle sensor output calibration
  
C1526
 [Resolver correction not completed]
 *1
 Delete diagnosis code
  
C1528
 [Motor rotation angle sensor]
 *1
 Once again, IG ON
  
C1531
 [ECU Malfunction 1]
 *1
 Once again, IG ON
  
C1532
 [ECU Malfunction 2]
 *1
 Once again, IG ON
  
C1533
 [ECU Malfunction 3]
 *2
 After normal operation is determined
  
C1534
 [ECU Malfunction 4]
 *1
 Once again, IG ON
  
C1541
 [Vehicle Speed Signal Failure 1]
 *1
 After normal operation is determined
  
C1551
 [Power Supply Voltage Failure]
 *1
 After normal operation is determined
  
C1552
 [PIG Power Supply Voltage]
 *1
 After normal operation is determined
  
C1554
 [Power Supply Relay Failure]
 *1
 Once again, IG ON
  
C1555
 [Motor relay abnormal]
 *1
 Once again, IG ON
  
U0100
 [Lost Communication With ECM/PCM “A”]
 *1
 After normal operation is determined
  
U0122
 [Lost Communication With Vehicle Dynamics Control Module]
 *1
 After normal operation is determined
  
U0416
 [Invalid Data Received From Vehicle Dynamics Control Module]
 *1
 Once again, IG ON
  
*1: Turns on
*2: Does not turn on
SYMPTOM TABLE
Power steering system
Symptoms
 Inspection items
 Reference pages
Steering operation is heavy
 Front tires (improperly inflated, uneven wear)
  
Front wheel alignment (improper)
  
Front suspension (lower ball joint)
  
Steering link ASSY
  
Torque sensor (integrated into the steering column ASSY)
 -
Power steering motor (integrated into the steering column ASSY)
 -
Battery and power supply system
 -
Speed sensor system
 -
Skid control computer (brake actuator ASSY)
  
Power steering computer ASSY power supply voltage and internal relay
 -
Power steering computer ASSY
  
The presence of continued operation under high load or dry steering
 -
Steering force required is different in the left and right directions or it is uneven.
 Torque sensor zero point calibration or rotation angle sensor output calibration are incomplete.
  
Front tires (improperly inflated, uneven wear)
  
Front wheel alignment (improper)
  
Front suspension (lower ball joint)
  
Steering link ASSY
  
Torque sensor (integrated into the steering column ASSY)
 -
Steering column ASSY
  
Power steering motor (integrated into the steering column ASSY)
 -
Power steering computer ASSY
  
While driving, steering operation does not change depending on the speed, or the steering wheel does not return smoothly.
 Front suspension (lower ball joint)
  
Speed sensor system
 -
Skid control computer (brake actuator ASSY)
  
Torque sensor (integrated into the steering column ASSY)
 -
Power steering motor (integrated into the steering column ASSY)
 -
Steering link ASSY
  
Power steering computer ASSY
  
CAN communication system
  
There is a thumping noise during power steering operation, when the steering wheel returns to the neutral position
 Front suspension (lower ball joint)
  
Steering intermediate shaft
 -
Steering link ASSY
  
There is a rubbing sound when the steering wheel is turned during slow driving
 Power steering motor (integrated into the steering column ASSY)
 -
Steering link ASSY
  
Steering column ASSY
  
Steering sensor (spiral cable SUB-ASSY)
 -
Rubbing of the steering wheel ASSY and the column cover
  
Power steering computer ASSY
  
An abnormal high-pitched squeaking sound occurs when the steering wheel is slowly turned when the vehicle is stopped
 Steering link ASSY
  
Power steering motor (integrated into the steering column ASSY)
 -
Steering wheel installation condition
  
The steering wheel vibrates (accompanied with a noise) during dry steering
 Steering link ASSY
  
Power steering motor (integrated into the steering column ASSY)
 -
Steering column ASSY
  
Steering wheel installation condition
  
P / S warning light remains ON
 Battery and power supply system
 -
Refer to the flow chart
  
HOW TO TROUBLESHOOT
1. Bring in the car


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2. Interview and phenomenon check


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3. Battery voltage check

(1) Check the battery voltage.
(2) Refer to parts location drawings and circuit figures and inspect any parts that can be checked visually such as blown fuses in the system, wiring harness open circuit, short circuits, or poor connector contacts.
NOTE:
If the battery voltage is less than 11 V, please recharge or replace the battery before commencing the diagnostic procedure.
(3) Use the SSM3 to check the [Battery Voltage Lo Record]. (Refer to )

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4. Check of diagnosis codes and freeze frame data

(1) Check of diagnosis codes and freeze frame data
(a) Record diagnosis codes and freeze frame data. (Refer to )
(2) Deletion of diagnosis codes and freeze frame data (Refer to )
(3) Diagnosis codes recheck (Refer to )
(a) Based on the recorded diagnosis codes and freeze frame data, recreate the trouble phenomenon and recheck for the presence of the diagnosis code output.
NOTE:
·If an error code for CAN communication system is output, first troubleshoot CAN communication and repair it. (Refer to )
·If communication with the power steering computer ASSY cannot be established by the SSM3, check the CAN communication between the DLC3 and the power steering computer ASSY, as well as the power steering computer ASSY IG circuit.
Result
Result
 Go to
Diagnosis code normal
 A
Error code output
 B
Diagnosis code normal, unable to check or recreate the phenomenon
 C
B
>Please refer to the list of diagnostic codes (), carry out troubleshooting for each code, and progress to step 7.
C
>Progress to “malfunction simulation” ().

A▼

5. Symptom table (refer to )

Result
Result
 Go to
Not applicable to the symptom table.
 A
Applicable to the symptom table.
 B
B
>Perform troubleshooting for each applicable symptom and progress to step 7.

A▼

6. Based on the trouble phenomenon, use the following methods to perform troubleshooting

(1) Current data display & save (Refer to )
(2) ECM terminal arrangement (Refer to )

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7. Adjustment, repair, or replacement


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8. Confirmation test


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Complete

CHECK LIST FOR INTERVIEW
CHECKING / CLEARING DIAGNOSTIC CODES
1. Reading the diagnosis codes
(1) Turn the ignition switch to OFF.
(2) Connect the SSM3 to the DLC3 connector.
(3) Turn the ignition switch to ON.
(4) Follow the SSM3 display screen to read the diagnosis codes.
CAUTION:
If an error is detected, recheck diagnosis codes after the issue is resolved and confirm that no error code is output.
2. Deletion of recorded diagnosis codes
(1) Turn the ignition switch to OFF.
(2) Connect the SSM3 to the DLC3.
(3) Turn the ignition switch to ON.
(4) Follow the SSM3 display screen to delete the diagnosis codes.
FREEZE FRAME DATA
1. Freeze frame data
NOTE:
·If an error diagnosis code is output, the freeze frame data at the time of the generation of the error code is recorded.
·When an error diagnosis code is generated and the freeze frame data is recorded, data is not updated or deleted until the recorded data itself is deleted (diagnosis code deletion).
(1) Turn the ignition switch to OFF.
(2) Connect the SSM3 to the DLC3.
(3) Display the error code on the diagnostic code confirmation screen. (Refer to )
(4) Check the freeze frame data.
List of freeze frame data
Item name
 Description/display range
 Normal value
 Remarks
Vehicle speed
 Indicates the vehicle speed input from the skid control computer.
Display range: 0.0 - 300.0 km/h
 0 km/h: When stopped
 -
No large variation: Vehicle is travelling at a constant speed
-
Engine speed
 Indicates the engine speed.
Display range: 0 - 12800 r/min
 No large variation: Engine speed is constant
 -
Motor current
 Indicates the current flowing to the motor.
Display range: -327.68 - 327.67 A
 Changes in proportion to the steering force: During engine start, steering operation
 Left turn (+)
Right turn (-)
Motor current (requirement)
 Indicates the requirement for the current flowing to the motor.
Display range: -327.68 - 327.67 A
 Changes in proportion to the steering force: During engine start, steering operation
 Left turn (+)
Right turn (-)
Steering angular speed
 Indicates the angular speed of steering operation.
Display range: -32768 - 32767 deg/s
 Changes in proportion to the steering speed: During engine start, steering operation
 Left turn (+)
Right turn (-)
Thermistor temperature
 Indicates the ECM board temperature.
Display range: -50.0 - 150.0°C
 -
 -
PIG power supply voltage
 Indicates the power supply voltage to drive the motor.
Display range: 0.0000 - 20.1531 V
 9 - 16 V: Always
 -
IG power supply voltage
 Indicates the ECM power supply state.
Display range: 0.0000 - 20.1531 V
 9 - 16 V: IG ON
 -
Steering torque
 Indicates the steering torque.
Display range: -7.00 - 7.00 Nm
 Changes in proportion to the steering force: During engine start, steering operation
 Left turn (+)
Right turn (-)
Motor rotation angle
 Indicates the motor rotation angle.
Display range: 0.000 - 360.000 deg
 Varies between 0 and 360 deg: During engine start and steering operation
 -
Motor current (Command Value 2)
 Indicates the requirement for the current flowing to the motor.
Display range: -327.68 - 327.67 A
 Changes in proportion to the steering force: During engine start, steering operation
 -
Boost voltage after the coil.
 Indicates the boost voltage after the coil.
Display range: 0.000 - 98.000 V
 Approx. 27 V: During engine start, steering non-operation
 -
Varies within 16 - 35 V: During engine start and steering operation
 -
Motor power supply voltage
 Indicates the motor power supply voltage.
Display range: 0.000 - 98.000 V
 Approx. 27 V: During engine start, steering non-operation
 -
Varies within 4 - 35 V: During engine start and steering operation
 -
Motor terminal voltage (U phase)
 Indicates the motor U terminal voltage.
Display range: 0.000 - 98.000 V
 Varies within 4 - 35 V: During engine start and steering operation
 -
Motor terminal voltage (V phase)
 Indicates the motor V terminal voltage.
Display range: 0.000 - 98.000 V
 Varies within 4 - 35 V: During engine start and steering operation
 -
Motor terminal voltage (W phase)
 Indicates the motor W terminal voltage.
Display range: 0.000 - 98.000 V
 Varies within 4 - 35 V: During engine start and steering operation
 -
Torque sensor 1 output
 Indicates the torque sensor 1 output.
Display range: 0.0000 - 5.0000V
 2.3 - 2.7 V: During engine start, no steering load (neutral position)
 -
2.3 - 3.8 V: During engine start, steering to the right
 -
1.2 - 2.7 V: During engine start, steering to the left
 -
Torque sensor 2 output
 Indicates the torque sensor 2 output.
Display range: 0.0000 - 5.0000V
 2.3 - 2.7 V: During engine start, no steering load (neutral position)
 -
1.2 - 2.7 V: During engine start, steering to the right
 -
2.3 - 3.8 V: During engine start, steering to the left
 -
Torque sensor 1 (zero point value)
 Indicates the torque sensor 1 output value at the zero point.
Display range: 0.0000 - 5.0000V
 -
 -
Torque sensor 2 (zero point value)
 Indicates the torque sensor 2 output value at the zero point.
Display range: 0.0000 - 5.0000V
 -
 -
WORK SUPPORT
1. Steering zero point calibration
CAUTION:
·Always perform a steering zero point calibration after replacing the steering column ASSY or power steering computer ASSY, or when there is a difference between the right and left steering force.
·When C1516 (torque sensor zero point calibration not finished) is recorded, please delete the diagnosis code as torque sensor zero point calibration is unable to be performed in this case. (Refer to )
·When C1526 (Resolver calibration not finished) is recorded, please delete the diagnosis code as rotation angle sensor output calibration is unable to be performed in this case. (Refer to )
NOTE:
For steering zero point calibration, delete the sensor calibration value and perform torque sensor zero point calibration and rotation angle sensor output calibration.
(1) Items to be checked before calibration.
(a) Use the SSM3 to check the [IG power supply voltage] with the [Current Data Display & Save]. (Refer to )
Voltage :  10 V or more
CAUTION:
As calibration cannot be performed if the IG power supply voltage is less than 9 V, please recharge or replace the battery before commencing calibration if this value is not within the specified range.
(2) Steering zero point calibration
(a) Set the steering and front tires to the straight-ahead position.
(b) Connect the SSM3 to the DLC3.
(c) Turn the ignition switch to ON.
(d) Select [Work Support] → [Steering zero point calibration] on the SSM3 display screen.
(e) Follow the SSM3 display screen to carry out the steering zero point calibration.
CAUTION:
·Do not touch the steering during the torque sensor zero point calibration.
·Do not do any fast steering operation during the rotation angle sensor output calibration.
(f) Check the diagnosis codes. (Refer to )
CAUTION:
·When performing steering zero point calibration, please confirm that the diagnosis codes are normal after the procedure is complete.
·If C1515, C1516, or C1534 are output, follow the procedure to perform troubleshooting for each diagnosis code. (Refer to )
CIRCUIT FIGURE
ECM TERMINAL ARRANGEMENT
1. Inspection of the power steering computer ASSY
(1) Check the voltage or resistance between each terminal, as well as between the chassis ground and each terminal.
CAUTION:
This check is performed from the back side of the connector, with the connector hooked up to the computer.
Captions in illustration
*a
 Connector not connected
(Power steering computer ASSY)
 -
 -
Criteria
Terminal No. (Symbol)
 Terminal description
 Condition
 Special conditions
z1-1 (V) [*]
 V phase motor output
 -
 -
z1-2 (U) [*]
 U phase motor output
 -
 -
z1-3 (W) [*]
 W phase motor output
 -
 -
A14-1 (PIG) - A14-2 (PGND)
 Motor power supply
 Always
 9 - 16 V
A14-2 (PGND) - Chassis ground
 Power supply ground
 Always
 1 Ω or less
A15-6 (IG) - A14-2 (PGND)
 IG power supply
 IG SW ON
 9 - 16 V
z2-5 (RZV) - A14-2 (PGND)
 Rotation angle sensor excitation output signal
 During engine start, steering operation
 0.68 - 4.42 V
z2-7 (RZG) - A14-2 (PGND)
 Rotation angle sensor excitation circuit GND
 Always
 1 Ω or less
z2-13 (RZCS) - A14-2 (PGND)
 Rotation angle sensor COS phase input signal
 During engine start, steering operation
 0.68 - 4.42 V
z2-14 (RZSN) - A14-2 (PGND)
 Rotation angle sensor SIN phase input signal
 During engine start, steering operation
 0.68 - 4.42 V
z2-8(TRQ1) - z2-11(TRQG)
 Torque sensor signal 1
 During engine start, no steering load (neutral position)
 2.3 - 2.7 V
During engine start, steering to the right (When the vehicle is stopped)
 2.3 - 3.8 V
During engine start, steering to the left (When the vehicle is stopped)
 1.2 - 2.7 V
z2-9(TRQV) - z2-11(TRQG)
 Torque sensor power supply
 IG SW ON
 4.5 - 5.5 V
z2-10(TRQ2) - z2-11(TRQG)
 Torque sensor signal 2
 During engine start, no steering load (neutral position)
 2.3 - 2.7 V
During engine start, steering to the right (When the vehicle is stopped)
 1.2 - 2.7 V
During engine start, steering to the left (When the vehicle is stopped)
 2.3 - 3.8 V
z2-11(TRQG) - Chassis ground
 Torque sensor ground
 Always
 1 Ω or less
*: As connector z1 is equipped with a lock lever, it is not possible to check each terminal while the connector is hooked up to the power steering computer ASSY.
CURRENT DATA DISPLAY & SAVE
1. Current data display & save item
(1) Turn the ignition switch to OFF.
(2) Connect the SSM3 to the DLC3.
(3) Turn the ignition to IG ON and select [Current Data Display & Save] on the SSM3 display screen. Check the items of [Current Data Display & Save].
SSM3 screen: [Power Steering] → [Current Data Display & Save]
Item name
 Description/display range
 Normal value
 Remarks
[Vehicle Speed]
 Indicates the vehicle speed input from the skid control computer.
Display range: 0.0 - 300.0 km/h
 0 km/h: When stopped
 -
No large variation: Vehicle is travelling at a constant speed
-
[Engine Speed]
 Indicates the engine speed.
Display range: 0 - 12800 r/min
 No large variation: Engine speed is constant
 -
[Motor Current]
 Indicates the current flowing to the motor.
Display range: -327.68 - 327.67 A
 Changes in proportion to the steering force: During engine start, steering operation
 Left turn (+)
Right turn (-)
[Command Value Current]
 Indicates the requirement for the current flowing to the motor.
Display range: -327.68 - 327.67 A
 Changes in proportion to the steering force: During engine start, steering operation
 Left turn (+)
Right turn (-)
[Steering Angle Velocity]
 Indicates the angular speed of steering operation.
Display range: -32768 - 32767 deg/s
 Changes in proportion to the steering speed: During engine start, steering operation
 Left turn (+)
Right turn (-)
[Thermistor Temperature]
 Indicates the ECM board temperature.
Display range: -50.0 - 150.0°C
 -
 -
[PIG-Power Source Volt]
 Indicates the power supply voltage to drive the motor.
Display range: 0.0000 - 20.1531 V
 9 - 16 V: Always
 -
[ABS_CM Power Voltage]
 Indicates the ECM power supply state.
Display range: 0.0000 - 20.1531 V
 9 - 16 V: IG ON
 -
[Steering Wheel Torque]
 Indicates the steering torque.
Display range: -7.00 - 7.00 Nm
 Changes in proportion to the steering force: During engine start, steering operation
 Left turn (+)
Right turn (-)
[Motor Rotation Angle]
 Indicates the motor rotation angle.
Display range: 0.000 - 360.000 deg
 Varies between 0 and 360 deg: During engine start and steering operation
 -
[Motor voltage (Command Value 2)]
 Indicates the requirement for the current flowing to the motor.
Display range: -327.68 - 327.67 A
 Changes in proportion to the steering force: During engine start, steering operation
 -
[PIG2 Voltage]
 Indicates the boost voltage after the coil.
Display range: 0.000 - 98.000 V
 Approx. 27 V: During engine start, steering non-operation
 -
Varies within 16 - 35 V: During engine start and steering operation
 -
[Motor Voltage]
 Indicates the motor power supply voltage.
Display range: 0.000 - 98.000 V
 Approx. 27 V: During engine start, steering non-operation
 -
Varies within 4 - 35 V: During engine start and steering operation
 -
[Motor Terminal Volt(U)]
 Indicates the motor U terminal voltage.
Display range: 0.000 - 98.000 V
 Varies within 4 - 35 V: During engine start and steering operation
 -
[Motor Terminal Volt(V)]
 Indicates the motor V terminal voltage.
Display range: 0.000 - 98.000 V
 Varies within 4 - 35 V: During engine start and steering operation
 -
[Motor Terminal Volt(W)]
 Indicates the motor W terminal voltage.
Display range: 0.000 - 98.000 V
 Varies within 4 - 35 V: During engine start and steering operation
 -
[Torque Sensor 1 Output]
 Indicates the torque sensor 1 output.
Display range: 0.0000 - 5.0000V
 2.3 - 2.7 V: During engine start, no steering load (neutral position)
 -
2.3 - 3.8 V: During engine start, steering to the right
 -
1.2 - 2.7 V: During engine start, steering to the left
 -
[Torque Sensor 2 Output]
 Indicates the torque sensor 2 output.
Display range: 0.0000 - 5.0000V
 2.3 - 2.7 V: During engine start, no steering load (neutral position)
 -
1.2 - 2.7 V: During engine start, steering to the right
 -
2.3 - 3.8 V: During engine start, steering to the left
 -
[TRQ1 Zero Point Value]
 Indicates the torque sensor 1 output value at the zero point.
Display range: 0.0000 - 5.0000V
 -
 -
[TRQ2 Zero Point Value]
 Indicates the torque sensor 2 output value at the zero point.
Display range: 0.0000 - 5.0000V
 -
 -
[IG ON/OFF Times]
 Indicates the number of times the ignition is turned to IG ON after the diagnosis code is detected.
Display range: 0 - 65535 times
 -
 -
[Heating prevention control history]
 Indicates the presence of an overheat protection control history.
Display contents: No/Yes
 -
 -
[Motor Lo Power Record]
 Indicates the presence of a PIG power supply voltage drop history.
Display contents: No/Yes
 -
 -
[Engine speed (RDY) signal loss history]
 Indicates the presence of an engine speed signal interruption history.
Display contents: No/Yes
 -
 -
[Spd Sig Invalid Record]
 Indicates the presence of a vehicle speed signal unavailability history.
Display contents: No/Yes
 -
 -
[Battery Voltage Lo Record]
 Indicates the number of battery voltage drop instances.
Display contents: 0 - 65535 times
 -
 -
[Confirmation of resolver correction completion]
 Indicates the resolver calibration completion state.
Display contents: Calibration completed/Calibration not completed
 -
 -
[Confirmation of torque 0 point correction completion]
 Indicates the torque zero point calibration completion state.
Display contents: Calibration completed/Calibration not completed
 -
 -
[Number of Diagnostic Code(s):]
 Indicates the number of stored diagnosis codes.
Display range: 0 - 255 items
 -
 -
FAILSAFE LIST
1. Failsafe list
(1) When the power steering computer ASSY detects a malfunction, to protect the system it suspends power assist or continues to perform control under special conditions.
Malfunction type
 Fail safe
·Torque sensor malfunction
·Motor rotation angle sensor malfunction
·Power steering motor malfunction
·Power steering computer ASSY malfunction (other than the temperature sensor system)
 Power assist is suspended.
Power steering computer ASSY malfunction (temperature sensor system)
·System overheat protection control is switched to a specification that doesn't use a board temperature sensor, and control is continued.
·Control is performed under a limited power assist level.
EEPROM error
 Control is performed under the default map.
·CAN Communication Error
·Speed sensor system malfunction
·Skid control computer (brake actuator ASSY) communication malfunction
 It is fixed to the same characteristics as when travelling at 100 km/h, and power steering control is continued.
When ECM internal temperature is high (not a malfunction)
 The power assist level is limited, or assist is temporarily suspended.
Power supply voltage drop (not a malfunction)
 The power assist level is limited, or assist is temporarily suspended.
NOTE:
·If there is repeated steering wheel operation when the vehicle is stopped or driving slowly, or the steering wheel is kept at its turning angle limit for a long period of time, the power assist level may be reduced in order to prevent the motor or computer from overheating. In this case, the system will return to normal if there is no steering wheel operation for approximately 10 minutes with the engine at idle speed.
·If the battery is not sufficiently charged or there is a temporary drop in voltage, the power assist level may be reduced and the P/S warning light may be turned on. In this case, it will return to a normal state when the battery voltage recovers.
DTCC1511 Torque sensor 1 abnormal
DTCC1512 Torque sensor 2 abnormal
DTCC1513 Torque sensor 3 abnormal
DTCC1514 Torque Sensor Power Supply Failure
DTCC1517 Torque sensor hold abnormality
Description of functions
The power steering computer ASSY uses the input signal received from the torque sensor to detect the steering force. As part of the fail safe function, power assist is suspended when a torque sensor system malfunction is detected.
DTC No.
 Detected item
 Inspection parts
C1511
 Torque sensor (TRQ1) signal malfunction, or interruption
· Torque sensor (integrated into the steering column ASSY)
·Power steering computer ASSY
C1512
 Torque sensor (TRQ2) signal malfunction, or interruption
C1513
 When the deviation of torque sensors TRQ1 and TRQ2 falls outside the specified value
C1514
 Torque sensor power supply voltage malfunction
C1517
 Provisional control continues for a long period of time due to a torque sensor system malfunction
Circuit figure
Inspection steps
CAUTION:
Always perform a steering zero point calibration after replacing the steering column ASSY or power steering computer ASSY. (Refer to )
1. Connector connection check

(1) Check the connection state of torque sensor connector z2.
Criteria :  The torque sensor connector is properly connected to the power steering computer ASSY.
Captions in illustration
*a
 Connector connected
(Power steering computer ASSY)
NG
>Connect it securely.

OK▼

DTCC1515 Torque Sensor Zero Point Adjustment Undone
DTCC1525 Resolver not corrected
Description of functions
After replacement of the steering column ASSY or power steering computer ASSY, a diagnosis code is output (when the power steering computer ASSY determines that torque sensor zero point calibration or rotation angle sensor output calibration have not been performed).
Calibration cannot be performed when the IG voltage is less than 9V.
DTC No.
 Detecting conditions
 Action item
C1515
 Torque sensor zero point calibration not performed
 Perform torque sensor zero point calibration. Operation is normal if a diagnosis code is not output.
C1525
 Rotation angle sensor output calibration not performed
 Perform rotation angle sensor output calibration. Operation is normal if a diagnosis code is not output.
Inspection steps
CAUTION:
Always perform a steering zero point calibration after replacing the steering column ASSY or power steering computer ASSY. (Refer to )
1. Diagnosis code check

(1) Use the SSM3 to perform steering zero point calibration. (Refer to ) *1
(2) Use the SSM3 to recheck the diagnosis codes. (Refer to ) *2
NOTE:
If an error code is output, repeat the procedures (*1 and *2) three times.
Result
Result
 Go to
An error code is output, even if steering zero point calibration is performed three times.
 A
No diagnosis code is output.
 B
B
>No malfunction (Returns to normal operation after calibration is complete)

A▼

2. Replacement of the power steering computer ASSY

(1) Replace the power steering computer ASSY. (Refer to )

Next▼

3. Diagnosis code check

(1) Use the SSM3 to perform steering zero point calibration. (Refer to ) *1
(2) Use the SSM3 to recheck the diagnosis codes. (Refer to ) *2
NOTE:
If an error code is output, repeat the procedures (*1 and *2) three times.
Result
Result
 Go to
An error code is output, even if steering zero point calibration is performed three times.
 A
No diagnosis code is output.
 B
B
>Completed

A▼
Replacement of the steering column ASSY (Refer to )

DTCC1516 Torque sensor zero point adjustment incomplete
DTCC1526 Resolver correction not completed
Description of functions
A diagnosis code is output if the power steering computer ASSY determines that torque sensor zero point calibration or rotation angle sensor output calibration have not been completed.
DTC No.
 Detecting conditions
 Action item
C1516
 The torque sensor zero point calibration was not correctly completed due to a problem such as touching the steering mechanism.
 Delete the diagnosis code, delete the sensor calibration value, and then perform torque sensor zero point calibration. Operation is normal if a diagnosis code is not output.
C1526
 The rotation angle sensor output calibration was not correctly completed.
 Delete the diagnosis code, delete the sensor calibration value, and then perform rotation angle sensor output calibration. Operation is normal if a diagnosis code is not output.
Inspection steps
CAUTION:
Always perform a steering zero point calibration after replacing the steering column ASSY or power steering computer ASSY. (Refer to )
1. Diagnosis code check

(1) Using SSM3, clear the diagnostic code. (Refer to ) *1
(2) Use the SSM3 to perform steering zero point calibration. (Refer to ) *2
(3) Use the SSM3 to recheck the diagnosis codes. (Refer to ) *3
NOTE:
If an error code is output, repeat the procedures (*1 - *3) three times.
Result
Result
 Go to
An error code is output, even if steering zero point calibration is performed three times.
 A
No diagnosis code is output.
 B
B
>No malfunction (Returns to normal operation after calibration is complete)

A▼

3. Diagnosis code check

(1) Using SSM3, clear the diagnostic code. (Refer to ) *1
(2) Use the SSM3 to perform steering zero point calibration. (Refer to ) *2
(3) Use the SSM3 to recheck the diagnosis codes. (Refer to ) *3
NOTE:
If an error code is output, repeat the procedures (*1 - *3) three times.
Result
Result
 Go to
An error code is output, even if steering zero point calibration is performed three times.
 A
No diagnosis code is output.
 B
B
>Completed

A▼
Replacement of the steering column ASSY (Refer to )

DTCC1521 Motor failure 1
DTCC1531 ECM Malfunction 1
DTCC1532 ECM Malfunction 2
DTCC1533 ECM Malfunction 3
DTCC1534 ECM Malfunction 4
DTCC1554 Power Supply Relay Failure
DTCC1522 Motor failure 2
DTCC1523 Motor failure 3
DTCC1524 Motor failure 4
DTCC1555 Motor relay abnormal
Description of functions
As part of the fail safe function, power assist is suspended or limited when a motor error diagnosis code is being output.
DTC No.
 Detected item
 Inspection parts
C1522
 Power supply current sensor malfunction
· Power steering motor (integrated into the steering column ASSY)
·Power steering computer ASSY
C1523
 Excessive motor current deviation (difference between the command and feedback values)
C1524
 Voltage malfunction or open circuit between motor terminals
C1555
 Motor relay (integrated in ECM) malfunction
DTCC1528 Motor rotation angle sensor
Description of functions
As part of the fail safe function, power assist is suspended when a motor rotation angle sensor malfunction diagnosis code is being output.
DTC No.
 Detected item
 Inspection parts
C1528
 Motor rotation angle sensor malfunction
·Motor rotation angle sensor (integrated into the steering column ASSY)
·Power steering computer ASSY
Circuit figure
Inspection steps
CAUTION:
Always perform a steering zero point calibration after replacing the steering column ASSY or power steering computer ASSY. (Refer to )
1. Connector connection check

(1) Check the connection state of motor rotation angle sensor connector z2.
Criteria :  The motor rotation angle sensor connector is properly connected to the power steering computer ASSY.
Captions in illustration
*a
 Connector connected
(Power steering computer ASSY)
NG
>Connect it securely.

OK▼

2. Read the SSM3 data (motor rotation angle)

(1) Use the SSM3 to check the [Motor Rotation Angle]. (Refer to )
SSM3 screen: [Power Steering] → [Current Data Display & Save]
Item name
 Description/display range
 Normal value
 Remarks
Motor rotation angle
 Indicates the motor rotation angle.
Display range: 0.000 - 360.000 deg
 Varies between 0 and 360 deg: During engine start and steering operation
 -
Criteria :  During engine start and steering operation, this varies between 0 - 360 deg.
NG
> Go to Step 3.

OK▼
Replacement of the power steering computer ASSY (Refer to )

3. Inspection of the steering column ASSY (motor rotation angle sensor)

(1) Disconnect the motor rotation angle sensor connector z2 from the power steering computer ASSY.
(2) Measure the resistance of the vehicle side connector.
Resistance
Inspection terminals
 Inspection conditions
 Standard value
z2-5(RZV) - z2-7(RZG)
 Always (23°C)
 27.6 - 41.4Ω
z2-14(RZSN) - z2-7(RZG)
 Always (23°C)
 75.2 - 112.8Ω
z2-13(RZCS) - z2-7(RZG)
 Always (23°C)
 73.6 - 110.4Ω
Captions in illustration
*a
 Front side of vehicle wiring harness connector
(Power steering computer ASSY connector)
NG
>Replacement of the steering column ASSY (Refer to )

OK▼
Replacement of the power steering computer ASSY (Refer to )

DTCC1541 Vehicle Speed Signal Failure 1
Description of functions
The power steering computer ASSY uses CAN communication to input the vehicle speed signal from the skid control computer (brake actuator ASSY).
DTC No.
 Detected item
 Inspection parts
C1541
 Vehicle speed signal abnormal
·Speed sensor system
·Vehicle stability control system
·CAN communication system
·Power steering computer ASSY
Inspection steps
CAUTION:
Always perform a steering zero point calibration after replacing the power steering computer ASSY. (Refer to )
1. Diagnosis codes check (CAN communication system)

(1) Use the SSM3 to check whether diagnosis code U0416 (VDC data error) is not being output. (Refer to )
Criteria :  U0416 is not output.
NG
>Progress to the appropriate diagnosis code (Refer to )

OK▼

2. Diagnosis codes check (Vehicle stability control system)

(1) Using the SSM3, check the Vehicle stability control system diagnosis codes. (Refer to )
Criteria :  No diagnosis code is output.
NG
>Go to “Vehicle stability control system (list of diagnostic codes)”. (Refer to )

OK▼
Replacement of the power steering computer ASSY (Refer to )

DTCC1551 Power Supply Voltage Failure
Description of functions
As part of the fail safe function, power assist is suspended or limited when there is a power supply system malfunction.
DTC No.
 Detected item
 Inspection parts
C1551
 IG power supply circuit is open or shorted.
·Power steering computer ASSY
·Power supply system
·ECM IG1 fuse
·Wiring harness or connector
DTCC1552 PIG power supply voltage malfunction
Description of functions
As part of the fail safe function, power assist is suspended when there is a PIG power supply malfunction.
DTC No.
 Detected item
 Inspection parts
C1552
 PIG power supply voltage malfunction
·EPS fuse
·Power steering computer ASSY
·Wiring harness or connector
DTCU0100 Engine data not received
DTCU0122 Lost Communication With Vehicle Dynamics Control Module
DTCU0416 Invalid Data Received From Vehicle Dynamics Control Module
P / S warning light remains ON
Description of functions
With normal diagnosis code output, troubleshooting is recorded if the P / S warning light remains on.
When the power supply voltage input circuit (IG and PIG) for the power steering computer ASSY is open, the P / S warning light remains on.
Circuit figure
Inspection steps
CAUTION:
Always perform a steering zero point calibration after replacing the power steering computer ASSY. (Refer to )
NOTE:
Before performing troubleshooting, check the fuse for this circuit.
1. Checking connection of each part

(1) Lightly jiggle the power steering computer ASSY connector and wiring harness in the up/down/left/right directions, and check the state of the P/S warning light.
Criteria :  No variation in the P/S warning light illumination state.
NOTE:
If operating properly, the P/S warning light comes on when the ignition is turned to IG ON and goes out after the engine has started.
NG
>Repair or replacement of wiring harness or connector

OK▼

2. Diagnosis codes check (CAN communication system)

(1) Use the SSM3 to check the CAN communication system. (Refer to )
Criteria :  No error code.
NG
>To CAN communication system (How to troubleshoot) (Refer to )

OK▼